We’re already seeing an increase in people who don’t seem to have much common sense. I want a community which is science and fact oriented

Common sense is incompatible with science. Science is about testing our fundamental assumptions, assuming nothing.

You might want to move your account over to mander.xyz and then browse mostly by Local rather than All or Subscribed.

In large measure what you are describing is considered by most people to be harmless - although it is actually not harmless at all.

Anyway, the good news is that this aspect is mainly "contained" within the communities that actually want that. As opposed to e.g. Facebook where it is everywhere (one presumes - I left it even before the pandemic).

There is an ENORMOUS amount of diversity on the Fediverse, more so than anywhere else I've seen, and nothing at all like Reddit unless you count the small niche communities, but even there... anytime a post would hit r/all people would comment like "brace yourself, the trolls are coming!", plus people in those niche subs would browse all and become tainted by it.

I was one of them. I started noticing how defensive my posture was getting, and becoming more snarky, and then even doing that irl at work. Therefore I left Reddit. I almost left Lemmy too, but I refuse to be that way. Us olds (or maybe you aren't old and instead only mature - or at least talk as if you are haha! 😂) know that we can touch grass and read books - social media is a privilege, not a "right", and not mandatory for my existence (although it is nice to keep up with things, other than having to use e.g. Google News, so I would have had to investigate finding a good RSS reader).

Reddit started to devolve when the "kids" came in and drowned out all the longer-form, more in-depth discussions involving actual facts, and replaced them instead with "I know you are but what am I?", "^This", "I also choose this guy's wife", etc. Which don't get me wrong - humor has its place in the world, it's just that when here are TENS or even HUNDREDS of such comments, IN A ROW, and they get upvoted whereas someone who writes a longer response gets actively downvoted, plus receives demeaning replies ("hey, tell it to someone who cares "), that is when I decided to quit Reddit. Whether I stay here or leave this too, I will not go back to Reddit. Or Facebook.

And most of that I blame the platforms for encouraging people to talk while actively discouraging them from listening. Notice that ads appear between posts, but not between comments, hence they encourage - with their UI elements and such - people posting. One example is how poor their internal search functionality is - oh well, it's easier just to post my question than to search for an answer. Another example is restricting pinned posts to merely 2 - when they could easily allow like 5 or 10 or something, especially if they allow a folder system. And then even the pinned posts would only show up as being pinned under certain conditions, which users of an app may not see. Omg and don't even get me started on their official app....... 🤮

On Lemmy, it is possible to have good conversations. Make liberal use of the block button to curate what you don't want though, bc moderation is in short supply, and what is there tends to be heavily biased, so e.g. a person behaving as a dick to someone else is likely to do so to you sometime later, so consider your future self's mental health as a priority:-).