Disco stands out at the Star Trek series that really commits to queer representation rather than shoving it in the background and/or discarding it (looking at you, Picard and to a lesser extent LD). At the end of season 3 I was floored when Stamets described Adira as his child because I could definitely see the found family trope progressing and was mentally joking he should adopt them, I just didn't expect it to pop up from subtext to text. It definitely feels like a more modern discussion of queerness than past series did.

...not sure how I feel about them destroy the subtlety of Trill as trans metaphors though. It's cool, it just feels very heavy-handed.

Well shit, now I need to go catch up on discovery. I’m not even sure where I left off!

That´s how I feel about it too. TOS is old Star Trek with weaknesses typical for the time, especially the sexism is horrible. Discovery on the other hand does not even feel like Star Trek but more like anti-Star Trek made by people who hate Star Trek and is just an overall bad tv show. That is of course only my personal perception and I am happy for everyone who has a good time watching New trek stuff.

Aside from a handful of episodes, TOS aged perfectly fine.

You'd be hard pressed to find any show with as many episodes and different writers that doesn't have a couple of shows with a bad take or two.