This is completely anecdotal but at least in my friends circle in the US a lot of people have stopped using Facebook (Messenger is different) or they use it for

This is completely anecdotal but at least in my friends circle in the US a lot of people have stopped using Facebook (Messenger is different) or they use it for very specific purposes like Marketplace, specific events, or major life updates. None of those are really engagement driving activities. It seems like most of Facebook's growth is coming from developing nations and older generations who are just now finding about it or haven't bothered moving on to other forms of social media.