(because there is a whole variety of fic that I simply cannot read with m/f but that doesn't trigger me at all when it's m/m or f/f).

That was something I was wondering if the story was commenting on, too! Because there *are* slash K/S stories where Spock totally expects Kirk to stop manwhoring around now that he has claimed him and their love is deep and true and what all. And in most of those stories Kirk is onboard with that. And it's true that it hasn't really pinged me as problematic there because it's not reinforcing heteronormative relationship expectations because it's slash--but that maybe it should ping as a problematic, unhealthy relationship in slash even so.

Thank you for taking the time to unpack your kink challenge fic for me. Honestly, this kind of discussion is what I read genderswitch/swap AUs for--to dissect characters' interactions and relationships and figure out how much of who they are is tied up in their gender identities. I don't know how much that's true for other readers, but this discussion definitely enriched your story for me.