Online platforms are not a substitute for real, in-person friendships. I forget the researcher who coined the term AI for "artificial intimacy": when you've got 1000 "friends" on social media but nobody to feed your cat when you go on vacation.

well it's not to say you can't have intimate online relationships.

Plenty of WoW groups from back in the day.

How many of those translated into long lasting, healthy real life relationships?

Can only speak for myself but I have several groups of people I've met online 10 or 20+ years ago, chat with online ranging from daily to weekly, and about half of them I meet in person once to several times per year. No clue if it's objectively a healthy relationship, but I'd say so. Obviously I'm not young anymore, and it should not matter I'm not in the US - but I don't see a meaningful difference here, because whether you can form these types of relationships today is a different question.

I find it hard to believe more than 2/3rds of the US are active on discord. That can't be right.

Probably many of those are people from other countries using VPNs.