Many of the nation’s top brands and celebrities have stopped posting on Meta’s new social network Threads — billed as a “Twitter killer” at the time of its splashy summer debut — as user traffic has plunged by more than 80%.

The National Football League, the wealthiest and most powerful sports league in the country, has not bothered to post on Threads in seven weeks.

Coca-Cola’s last post on Threads was a week ago while fast food giant McDonald’s hasn’t provided fresh content on the app for nearly two months.

Madison Square Garden’s official Threads account has not posted anything new in three months since first joining the app.

Five days after Threads was unveiled in July, parent company Meta revealed a staggering100 million users had signed up — nearly half of the 225 million active daily users that are on X, the social network formerly known as Twitter that’s now owned by Elon Musk.

Meta, however, achieved the eye-popping figure mainly because it automatically grants Instagram account holders with their own Threads page.

At its peak in July, Threads drew an average of 49.3 million daily active users on Android, according to the research firm Similarweb.

That number has since dipped to 8.6 million — an 82% drop.

The Similarweb statistics were first reported by The Information.

The steep drop in traffic has prompted Meta staffers to brainstorm ways to reignite interest in the app as celebrities including Oprah Winfrey and Will Smith — who have largely shunned X, the app formerly known as Twitter — signed up for Threads but have posted little since.

Emily Austin, a social media influencer and podcast host who boasts more than 24,000 followers on X, told The Post that she was among a group of creators recently invited by Meta to participate in a pickleball tournament in New York City.

“My friend who does influencer marketing at Meta invited me [to the tournament],” Austin told The Post.

Austin said that while she wasn’t offered any money to post exclusively to Threads, the outreach by Meta has boosted her motivation to post more on the app.

“They said they invited those who reflect Meta’s values to the highest regard,” Austin told The Post.

The Post has sought comment from Meta.

The rollout of Threads has added another wrinkle to the rivalry between billionaire foes Musk and Meta CEO Mark Zuckerberg.

During Musk’s tenure as owner of X, advertisers have fled while critics allege he has allowed hate speech to run rampant.

Meanwhile, Threads has quickly earned a reputation for being boring as a result of Zuckerberg’s emphasis on creating a “safe space” that avoids hard news and controversy.

Zuckerberg told The Verge last week that his company “set the culture for Threads” to be “a more positive, friendly place for discussion will hopefully be one of the defining elements for the next decade as we scale it out.”

“We obviously have a lot of work to do, but I’d say it’s off to quite a good start,” Zuckerberg said.

Musk, meanwhile, has panned Threads as “Instagram minus pics.”