Why is reddit like this?

Out of all the social media apps i’m on reddit has to be one the top for miserable people. Everyone is entitled to their own opinion and everyone may not agree but it’s to a point i can’t tell if people are really that mentally unstable or they’re joking and i mean that in the nicest way i can. With twitter i can tell they’re joking or you just don’t take it seriously but here it’s like always so negative. I can’t even enjoy a subreddit without it being some argument, sensitive or just nasty people. Everything is so controversial. Genuinely asking like is this what reddit is about , was it always like this? Please let me know i will gladly leave.