struck you the most
"I can not think of any cultural circumstance that justifies finding same-sex marriage to be immoral/wrong."
Sure. However, the existence of a law banning same-sex marriages speaks completely differently. And not the only old generation supports the ban. Of course, most people are more than neutral about this, but they do not like aggressive propaganda of same-sex marriages. Going into details is already discussing politics. "My memory on this is a little foggy, but from what I remember, during the 20th century the political climate and leaders were really hostile toward composers, such as Shostakovich. Also, I remembered something earlier from my world music class (thankfully I have stuff still saved from that class, so I was able to get details outside of my memory): In 1648, Czar Alexis I of Russia straight-up banned the use of musical instruments. I'm not sure how long that lasted, but that's pretty horrible. Not that other nations didn't experience oppression toward music.
It's just... when I think of Russia and music history these are the things I think of, sadly."
As you said, Not that other nations didn't experience oppression toward music. Maybe struck you the most that in USSR was problem with music, and that's true, because in those days there was a total censorship of EVERYTHING. But now everything is much calmer, especially with music.