And that it’s objectively homophobic for a policy to exist forbidding same-sex marriage while permitting heterosexual marriage?

Yes!

Do you acknowledge that some countries like the US which allow gay marriage materially harm lgbt people more than some countries that have banned gay marriage? Or is it only homophobic when it impacts your middle class ass?

Do you acknowledge that many socialist countries are progressive and moving toward more rights, and just starting from a worse starting point because of violently enforced colonial attitudes from countries that now claim to be progressive?

Do you acknowledge that Cuba, a socialist nation that you'd accuse of being tankie, is the place where lgbt people have the most material rights?

Do you acknowledge that communists have led every single queer liberation movement that has forced concessions from ruling governments? Or do you want to whitewash the communists out of stonewall?

You … you do realize that trans people and other “queerer” people than me engage in same-sex marriage too, right?

Yes, I'm one of them. And I'd happily give up my right to be married if it would erase queer homelessness, and erase conversion therapy camps, and erase the continual murder of black and indigenous trans women in our society.