Part of what keeps Reddit free of such nastiness (in my experience at least) is the downvote button. Sure, it creates an echo chamber that ruins the popular subreddits, but on the smaller subreddits, it means that anything toxic, inflammatory or misleading is nuked into invisibility. After getting used to this, I find it really hard to participate in places like youtube, Discord or old-style forums where conversations can be derailed or turned toxic by only a few bad actors.