From what I've seen it depends on the subreddit. Subreddits focusing entirely on political or social issues are almost entirely "safe-space" hugboxes where you can go to have one opinion validated and all others mocked. A sub focusing on, i dunno, model trains or something, you're not gonna have a lot of passion filled arguements, unless it's about some thing that interests only model train nerds and is completely irrelevant to the rest of the world. Something like the Ask Me Anything subreddits can have anything from the president of the US (or, let's be realistic, his PR team) to a vaccuum repairman doing Q&A's. I don't frequent any subreddits and mostly get linked to them from other forums, so I have no idea how to navigate the site beyond the obvious.
It's like how overall tumblr is known as the SJW hub for broken whiny crazies on the net, but realistically most of it is just porn. A bunch of porn. The SJW mob are just a small fraction of the site from the stats I've seen. Just a very loud and obnoxious fraction.