Hard to explain objectively; I think the things that turned me off to reddit back then (now it's more mainstream) were people's willingness to assume tons of knowledge of topics they didn't really know about, the general white, upper middle class male from the burbs tastes of things like r/music and other cultural subreddits. It felt like walking into a videogame fraternity and realizing I didn't belong there.
That's a highly subjective opinion...but it's how I felt. r/shitredditsays probably captures a bit of what made me uncomfortable.
There's certainly a white fraternity feel in a lot of reddits, so I can imagine how people can feel disconnect to it. But /r/shitredditsays, well... I was subscribed to it for some time, and the posts themselves do a good job at noticing really bad behaviour on reddit sometimes — but then I discovered the comments there, and I must say, it feels like half of the users of this sub are trolls who pretend to be THE worst strawmen feminists/SJW (I hate this term, but since we're talking about strawmen, I think it fits) ever. Just saying.
The SRS sidebar makes it pretty clear that the whole SJW façade is exactly that: a façade. They obviously have legitimate complaints but hyperbolise everything to poke fun at it.
Genuinely curious: why?