I’m not sure I ever really experienced “very early” Reddit, but this tracks with my experience as well. Smaller community, for better and for worse. Less “empty discussion” and quips. But also a lot more people who are, as you put it, “unglued”.

I think the lack of flamewars is more due to critical mass - you need a critical mass of people willing to waste time on that - than culture. There are definitely some communities I see here that do not have a friendly feel.