I thought pronouns are linked to gender. You can be female, male or non-binary. If you want to introduce a new gender, it's logical to use specific pronouns. But liking cats is not a gender, it's another species...
To answer your question, #1 is not valid to me. Since when "you can't do that" is an argument? I mean language can evolve.
For #2, I a...... reply
Honestly, I don't care... ima call you what you want me to call you. even if I find it weird I don't care and ill still call you by what you want reply
I'll just use whatever pronouns they want people to use. I'm not gonna disrespect their decision and make them uncomfortable. People use "xer/xem" and I respect that. Even if I have a different opinion than someone and could be considered offensive, I'd rather just keep it to myself so it doesn't harm anyone or cause any problem. 1 reply
Tell him “ur humor is just as disappointing as u r.”
If he doesn’t stop, just fucking donate him to the Salvation Army at that point. U could get a better brother and better humor at Wish.com reply