I use messenger to get in touch with people I have no other contact info for.
I use marketplace because Craigslist is a ghost town.
The things other platforms don’t do better is “have a near ubiquitous user base”.
I haven’t used Facebook as social media for at least a decade
Assembling the right mix of mechanics to perfectly match your setting/character concept is a whole game in itself. Sometimes I’ll just build a character for the fun of it.