Why are people on Q&A sites so mean ?

This sites just used for shits and giggles Reddit has too many bots and rules everyone thinks everyone is a troll. Girls Ask Guys is worse not only the site lags when you try to sign up but one mistake in a question everyone thinks you're a troll. I made a mistake in one question people started bullying me i tried to explain what happened but they didn't listen i deleted my account. When YA was up and this site was EP everyone was nice and helpful now no one is that anymore since YA shut down. I can see every Q&A site being like Yahoo being shut down in a year or two only nice site is Quora the one site you can't add details to a question and nobody reads the comments. Why are Q&A sites so mean now ? Are there any nice ones left ?