Why are people mean to me on yahoo when I am not mean to them it’s not nice?

Because people can hide behind their computers without you knowing who they are.

Because they are behind a screen and it makes them very brave.

people can act mean here cause they hide behind a screen..dont let them hurt your feelings ,ignor them

It is just easy to mouth off behind a keyboard . Really you should be realistic about who they are and the likelihood is they don't actually have any feelings for you or mean what they say .

Yeah there are sick people here like everywhere else!
Don't care...

One of the reasons people are mean to you is because you're a points troll who posts garbage answers to questions to harvest points so you can aks more questions. That's annoying as Hell and a violation of the Community Guidelines.

probably frustrated by so many aw snaps and page unresponsive or censored.

Some people delight in tearing down others. Many are probably not pleasant to be around in real life either.
For some it's due to anonymity though. They see you purely as your avatar /name and associated words, in the question or answer.

I have no idea ask them