Sorry that someone telling you, essentially, "Don't be shitty to people who are different from you" is a left vs right ideological issue for you.

As a society I think it's a good thing that we are increasingly stigmatizing open bigotry.

No, it's not. It's asking you to simply not post nasty stuff. It doesn't mean you have to embrace other cultures, sexualities or whatnot. It doeesn't even mean you have to like them. It just means keep any nasty comments about such things to yourself (or go say it elsewhere).

It's a really sad time for humanity if common courtesy is now considered "left-wing".

What most "right-wing" thinkers ignore is the fact that they consider excluding others IS THE REASON that people exclude THEM.

That's also part of what is freedom. Your freedom ends at the point where you limit the freedom of others. Otherwise the other person wouldn't be free.

That's also why most non-right-wing thinkers don't consider that another point of view, but simply selfish and asshole-ish.

Therefore if you want to argue your point, maybe you shouldn't highlight what you fight AGAINST (i.e. "left-wingers out", "refugees out") but what you fight FOR, which in some regards also boils down to respecting each other's freedom, right? Show that and you will find that doors will open for discussion.

I personally discuss with both people who would be defined as left-wing as well as with people who would be defined as right-wing. Both sides have reasonable people and some reasonable arguments, that are sadly sometimes hidden underneath many layers of bullshit.

Off topic but is transphobic a word the way it is being used. Shouldn't it be trans-a-phonic. Transphobic sounds like being afraid of vampires..