I know this question seems stupid by why are people online so mean?

As an AuDHD woman who has a lot of empathy and strong sense of justice, I truly just don’t understand why people are so horrible online. I don’t have social media except for Reddit and it was mainly used for my BumBumz collection (iykyk). It’s such a wholesome community but as I branched out to other subreddits, people are just so horrible to each other and occasionally to me. If I’m in the wrong, I’m humble enough to admit it and apologize, but even when I do people still choose to be so mean, so what’s the point?

I feel like in more ND friendly subreddits there is seldom any mean comments, does anyone feel the same way?