I was in the same place you are now but looking for places to discuss philosophy and looking at the state of mainstream sites like Reddit I decided the open web isn't a place for such discussions because of the sheer volume of noise.

I think the best place to discuss most things nowadays is the real world, but it takes time to build connections in the real world. HN is still a place of real productive discussions but not without a lot of moderation and even so it's still barely functional.