Reddit’s early days were similar, but internet culture has definitely gotten more intense since the early 2010s.

Has it really been that way? I've been on reddit since 2010 and from what I remember it was definitely much more nerdy and full of tech people who live on the internet, but I don't think it had much in common with what we call "terminally online" today. I associate "terminally online" with people who really care about things like culture wars and trying to push their views on others, spending a lot of time arguing about it. Whereas reddit in 2010 was much more homogenous - the stereotypes about forever alone IT nerds with nerdy hobbies were much more true than now, but that meant there were nowhere near as many cultural things to argue about. People sometimes had really weird or controversial opinions, but there was not a lot of added toxicity about it that's omnipresent now in the discussions.

Ime the "terminally online" problems with toxicity and culture wars only started around 2014-15 with the rise of "online feminism", that seemed like the first big division into two hostile groups that spent significant time just attacking each other.