I think you’ll find game design has equally influenced how people act online.
Yes, it’s true that people are different now-- but you are hilarious misinformed if you think dungeon finder is anything but anti-social. Saying ‘Hi’ is not making friends by the way.
It is impossible to make any meaningful interactions when everything is designed to go-go-go. There is no time or most importantly need to make any.
If you think “Well, the effort should be made by YOU.” then you clearly are entirely clueless on how social environments work, in games and indeed outside them. It’s called social culture, and it is determined by many factors.