Sorry the experience changed for you. Reminds me of the Buckethead forum buckethead.tk. I used to love that place, and there was a strong core group, but then his song “Jordan” was featured on Guitar Hero 2 and suddenly there was a massive influx of new fans coming to the forum and acting like they knew everything about him, many very young and immature. I hung around for a while, but eventually, most of the old guard left.
I use Letterboxd mostly as a video diary, to review things, and find new things to watch. I look around a bit, and I know there’s a lot of nonsense, but I mostly keep to myself there, so the experience has been pleasant for me, by and large. Most interactions have been positive, but then that’s because I only engage with reviewers that don’t annoy me. Haha.