For better or worse, my #fediverse posts are still out there, even the ones from mid-2009. I got my emails from the mid-1990s.
Barring an EMP, I'll be able to read my stupid hot takes and see my bad photos when I'm 85 living in nursing home. I will be able to reminisce about my youth. Not much different from having a diary or a stack of old letters.
I fear corporate social media will deny that experience for many people.