I am the wrong person to say this to you, and I apologize in advance.

My oldest son is not neurotypical. Raising him was a real challenge. When he was 8, he spent 6 weeks psychologically torturing me. He didn't care about my feelings and he found my reactions amusing. Part of what I told him that finally got him to stop was "The point at which you will care about my feelings is the point at which you want something from me and my reply is No. What have you done for me instead of to me here lately?"

You aren't responsible for anyone else's feelings. But if you routinely disrespect and offend people and then defend your right to crap on others instead of apologizing, that will have consequences for you and they won't be ones you will like. Most people are not as forthright as I am. Most people will never tell you "I am turning down your request because of all the times you were inconsiderate, insensitive, etc." They will just tell you No and not explain why.

I will suggest there may be a connection between how frustrated you seem to feel with other people and your general attitude that their feelings are not your problem. If everyone dislikes you, that can very much be a problem for you.

>I do not accept responsibility for feelings of offense others may feel in response to my speech.

If you know some people will be offended by a particular usage and you choose to use it anyway, then you are responsible for the resulting offence, whether you accept it or not.

Sometimes there are benefits which make the offence worthwhile, particularly when the offence is exceptionally uncommon. But using gender specific speech in generic/unknown contexts has no such benefits, and will cause offence fairly often. Singular they is easy and idiomatic, and I don't see any real excuse not to use it, other than laziness.

>It's not my job to manage their emotional state.

No, it's just a nice thing to do.