What would we be watching in an alternate, pandemic-free universe?

One choice would be the third season of “Atlanta,” the critically adored show created by Donald Glover, which would have made its debut a few weeks ago. Viewers would have also learned the latest in the saga of the Roy family on “Succession,” or could have tuned in to see the portrait of Monica Lewinsky and Bill Clinton in the new installment of “American Crime Story.”

The new seasons of those shows were postponed, and they won’t be available any time soon. The pandemic created a break in the boom time known as Peak TV, a gilded entertainment age of limitless home-viewing options ushered in by deep-pocketed tech companies and the cable networks desperate to keep up.

Nearly a year ago, when the full force of the coronavirus pandemic hit the United States, home viewing became the main leisure activity for those who found themselves working remotely and unable to go out in their off hours.

Cable news scored record ratings. Unscripted series like “Tiger King” and “Too Hot to Handle” became some of Netflix’s most-watched shows. Vintage escapist favorites like “The Golden Girls” had a resurgence.

As the virus continued to ravage the country, viewers found relief in new seasons of “The Mandalorian” and “The Crown,” as well as newcomers like “Bridgerton” and “The Queen’s Gambit.”

But pandemic-related production delays, which all but shut down the filming of scripted shows and films for much of 2020, have started to have an effect. The number of premieres of American scripted shows nose-dived in the second half of last year, a trend that is likely to continue for several months. And in 2020, for the first time in a decade, there were fewer new scripted shows to watch than in the previous year.

“The disruption of the pipeline is being manifested now,” said Matt Roush, a senior critic at TV Guide Magazine. “Now there are only a couple things a month to get excited about, versus getting excited a couple times a week before.”

A Sudden Drop

The rise of cable put a dent in the traditional broadcast TV schedule, one of fall premieres and springtime finales, that had dictated viewing habits for decades. And the entry of Netflix and other streaming services smashed what was left of the old model. Audiences got used to new shows popping up all the time.

From 2009 to 2019, the number of scripted shows in the United States went up each year, according to the research department of the cable network FX, one of the few organizations that kept track of the boom. In 2009, there were 210 scripted shows, according to FX. By 2019, there were 532, a 153 percent jump.

Before the pandemic, 2020 looked as if it would be the biggest year ever, thanks, in part, to the arrival of the streamers Disney+, Apple TV+, Quibi, HBO Max and Peacock.

From January to May, 214 adult-oriented American scripted shows had their premieres, according to Ampere, a research firm that tracks television distribution and production activity. That number was more than all the scripted shows in 2009. And it was a 32 percent jump over the number of scripted programs that made their debuts in the equivalent period of 2019.

In June, the industry hit a wall. In the second half of the year, premieres of scripted shows dropped 28 percent from the same period in 2019. The effect was most apparent in September, a big month for debuts. In September 2019, 86 shows had their premieres in the United States. A year later, that number fell to 35.

“Last year saw a stalling of what seemed like unstoppable growth for scripted content,” said Fred Black, a senior analyst at Ampere.

Nearly every platform, broadcast network and cable channel has taken a hit, according to Ampere. Even the prolific Netflix had fewer American scripted shows in the second half of last year. And the industrywide decline continued into January, Mr. Black said.

For some people in Hollywood, not to mention many viewers, the pause is not unwelcome.

“The more and more and more thing — who was that good for?” said Willa Paskin, a TV critic at Slate and a host of its “Decoder Ring” podcast. “We are ravenous content monsters, but isn’t it nice to have it be chiller and have some time to get to catch up on something?”

Naomi Fry, a staff writer at The New Yorker who covers pop culture and television, said: “For the last year, it feels as if we’ve been watching TV on a plane. We’re kind of locked in a vortex, flipping between various options. You’re waiting for time to pass. Some of it is very good, but there’s also a sense of glut and not a sense of excitement and specialness about it.”

One reason for the drop is obvious: With productions shut down, new seasons could not be completed in time. But there was another reason, executives and agents said. When filming resumed, extensive safety protocols for actors and crews added roughly 30 percent to most production budgets, said Chris Silbermann, the chief executive of ICM Partners, a major Hollywood talent agency.

“Everyone saw these costs pulling through the system and realized, ‘Oh, no, we’re going to have to do less,’” Mr. Silbermann said. “Stuff that was on the bubble, a lot of that stuff just went away.”

The slowdown also meant a change in Hollywood negotiations.

“I am now having tough production budget conversations with the streamers that I used to have with NBC, CBS, ABC and Fox,” Mr. Silbermann said. “These are like old-school budget conversations.”

Several outlets fed the maw in another way, by turning to international programming. Netflix’s “Lupin,” a French thriller series, and “Call My Agent!” a French workplace dramedy, have connected with American audiences. Their success was part of a larger lockdown trend: The viewing of non-English-language titles by U.S. Netflix subscribers shot up more than 50 percent in 2020, a Netflix spokesman said.

“Every show in another language is immediately better for us, because you can’t be on your phone,” Ms. Paskin, the Slate critic, said. “It just makes you pay attention.”

How About a Nice Game Show?

To fill the void left by the lack of scripted fare, nearly all outlets have also turned to reality programs, documentary series and even game shows, all of which are cheaper to make. Broadcast networks have given prime-time hours to shows like “Celebrity Wheel of Fortune” and “The Price Is Right at Night.” The number of unscripted shows making their debuts in 2020 increased 19 percent over the previous year, Ampere said.

“Everywhere you look, there’s a game show,” said Mr. Roush, the TV Guide critic. He added that his readers had pestered him about the lack of new episodes of network standbys like “NCIS” and “Grey’s Anatomy.”

With movie theaters either closed or selling limited tickets, streaming platforms have also filled in the blanks with new films that would have played on big screens for weeks or months before reaching home viewers. “Wonder Woman 1984” was the first of many WarnerMedia movies to stream on HBO Max the same day as its theatrical premiere date, and the much-anticipated Eddie Murphy sequel, “Coming 2 America,” arrives to Amazon on Friday.

Some TV franchises found ways to work around pandemic shutdowns. AMC’s biggest hit, “The Walking Dead,” was scheduled to go into production in April and start rolling out its 11th and final season in October. With 22 series regulars and hundreds of extras and crew members, it is not a simple production. Then the virus struck.

“We were sitting around asking ourselves, ‘What are we going to do?’” said Dan McDermott, president of original programming for AMC Networks.

They decided on a scaled-down add-on to the 10th season, with six new episodes focused on individual characters that could be shot sans dozens of zombies. Those episodes went into production in October, and the first is scheduled for AMC on Sunday. The 11th season of “The Walking Dead” started filming weeks ago, with the premiere scheduled for later this year, roughly two years after the debut of the previous season.

Several other AMC series fell a year behind schedule. Mr. McDermott said he had filled the holes with international acquisitions, including the British crime dramas “Gangs of London” and “The Salisbury Poisonings.”

“We’re discovering like, wow, there’s a lot of great content being made out there,” he said. “And it would not necessarily have enjoyed the same profile, if it were a regular year.”

There is still plenty to watch. The broadcast networks are offering new episodes of “This Is Us” and “Young Sheldon,” and Disney+ is streaming new episodes of the Marvel series “WandaVision.”

But with the spigot slowing as the stay-at-home period continues for millions of people, many viewers are turning to old favorites or trying shows they may have missed the first time around, like the cult NBC comedy series “Freaks and Geeks,” which became available on Hulu in January, or “The Sopranos,” a perennial HBO favorite.

“People have a lot more time to watch TV,” Ms. Paskin said. “People who say, ‘Oh, I’m going to watch “The Sopranos,”’ they are looking for a project. Doesn’t that just seem very quarantine mind-set? People are home every night. It’s fun to have a project that’s painless — rewatching ‘The Sopranos.’ Are you kidding!”