 Meta says its new social media site, Threads, is growing, but has not surpassed the site formerly known as Twitter. More from NPR's Bobby Allen. Meta's Threads is about a year old and now has 175 million users. That might sound like a lot, but it's a fraction of Instagram's more than 2 billion users. And even Elon Musk's ex, which has been declining, has three times as many users as Threads.