Metafilter has just about the highest groupthink quotient of any site I know of. Every single post ends up being about social justice, even when it isn't.
About two years ago I tried membership in The WELL, the semi-mythical web community that used to be featured in the printed booklets that came with 28.8kbps dial-up modems.
The retro interface was nice but the populace was incredibly homogeneous and everything was saturated with San Francisco liberal politics. I concluded that the insurmountable joining fees led the website to be frozen with a small self-referential community.
I've made reddit more enjoyable in the past by using plugins that auto collapse comments past depth 1 or 2. On avg, conversation devolves past that point.
I've since quit Reddit but comments here have convinced me to take a second look. I think this time around I will put even more filters in place, like no subreddits with over 10k subs, and some way to hide everyone's karma count including my own.
I guess what I'm trying to say is maybe you and I don't need a pay wall to filter, we just need an opinionated browser plugin (or easy way to share settings in RES)
This exists: https://www.metafilter.com/
The fee is $5 which turns out to be an insurmountable barrier for just about everyone. I personally like the site very much.