I noticed the same a couple months ago. After the API shutdown stuff happened, I largely left reddit. I would only go there for things I needed, like information and news related to my field.
But in October, I started going back more, and even commenting. And almost immediately, I got the "well ackshually..." comments and just so much unneeded aggression. People just looking to be right by ignoring 99% of the correct information in a comment and focusing on that 1% that's weak or, sure, wrong. And it was over dumb stuff, too.
After being on reddit for 13yrs straight, I guess I learned to be blind to it all. Like I knew it was happening, I saw it all the time, and I'm sure I know I even did it myself here and there. Hell, I was/am still a mod on a reddit; I saw it everyday. I did start getting tired of reddit and redditors about a year ago, but I just kinda brushed it aside.
Anyway, it wasn't until leaving and going to Beehaw and Tildes for a few months, and then going back, that I realized how bad it actually was on reddit. It's so glaring to me in threads all over the place. And that there was no desire to improve or change things. That that's just reddit's culture and that's how redditors like it.
As such, I've still kinda kept some distance from reddit. I'm still there, but I don't think I'll ever go back to how I was using the site pre-APIgate.
Further, I actually get angry when I see people on Lemmy engage in that redditesque way of just looking for confrontation and being smartasses. We left reddit; why are we bringing that mentality with us? If I saw someone on a Beehaw community acting that way, I call it out.
That's one of the reasons I support Beehaw potentially leaving Lemmy to do its own thing. I see Tildes and see how a standalone forum and community can exist and function well and productively, without all the "gotchas" and just unnecessary aggression. That's not to say Beehaw (or Tildes) is perfect. That behavior can be found everywhere. But at least there's a desire to try to stamp that out.