Internet is a reflection of human nature, we've been doing this for millenia, we can just access specific bubbles of groupthink far faster and more efficiently than ever before. The internet has been like this since people first started typing their thoughts and opinions where other connected people could see them.
Our problem isn't groupthink and bubbles of circle-jerking, our problem is our lack of attention-span and lack of patience, qualities that used to let us communicate and compromise with each other, now we're all too brain-rotted to even form romantic relationships, too drained to try to even engage with people who don't think the same way.
It's fine that communities circle-jerk, sometimes those even become wildly successful movements in society. What's not fine is we're all so used to fucking scrolling that we don't make effort past that circle-jerking anymore.