Mid 30's here and I joined right after the .edu requirement was dropped. Everyone in my age group is on Facebook but they rarely post anymore because they are busy! They all have kids and jobs and house projects they are working on and the novelty of updating about everything has worn off so they post very infrequently. When Gen-Zers make jokes about Facebook being for old people, that's us!
The algorithmic feed can't handle the "lack" of new posts though so it keeps inserting lots of ads, videos, and whatever that I don't actually care about. I really like Facebook when it is about interacting with my friends but everything else is a distraction. The level of distraction in Facebook is just too high. It's okay if nothing is going on!