Stop thinking like that. As a teen/college student I used both and nowadays I barely touch these "services" (rather psychological malware).
I suppose I migrated to my Kindle?
There are alcoholics who have dozens of drinks a week and there are people who responsibly augment a night of socializing with a drink or two. Alcohol isn't fundamentally irredeemable because some people develop problems, and neither is social media.
* Gamers are either tech-savvy or always have friends who are.
* Gamers stick to their small communities and leaders. If you superstar and announce that you're leaving Facebook nobody will follow, but gamers always follow their group / clan / whatever leaders.
* Also there is at least few companies like Valve, Blizzard, Epic Games who hold huge part of the market and have extremely loyal customers. They could certainly manage to set competition for Discord if there will be opening.
(I never had a Facebook account to begin with.)
Most people didn't lookup throughout the whole 20 minute train ride.
For social media making everyone connected, it sure has made everyone else more isolated with each other.
I would further observe that in a way, people have more of a shared experience today because of social media & internet in general.
We're still social creatures, just in a different way today. Admittedly, it's different from the days of yore, when people would hang out at the general store (or bar) and chat with the general community of people who passed through. But those days ended long before the Internet came along.