To confused people exploring from all Communities trying to understand what the hell is going on:
Bethesda is a game studio who does a decent job of giving people choice to do/be whatever they want in their games. Out of the box they included the option to choose your pronouns in a new game called "Starfield".
They also make it possible to modify their games to make very drastic changes to the player experience.
Nexus is a site that hosts thousands of mods to all sorts of games. People make mods, upload them to Nexus and players download them.
Someone made a mod to remove the option to choose pronouns from Starfield.
Nexus decided they don't want to host this mod. It's hurtful to people and goes against their values of inclusivity.
That's about it. Most of the people whinging about censorship don't even play the game. They're just here to whinge about how the world is moving on from old bigoted ways and they want to stay in the past and be jerks to people for merely existing. If they actually cared, they'd just download the mod from some other site. The mod itself is probably not much bigger than this reply.
In undue fairness, a mod to downgrade nudity or vulgarity would kinda make sense, if someone personally didn't want to see that. (Or if they were concerned about it for streaming. Or they had kids in the room.) For example, there's some racial slur graffiti in Bioshock Infinite that is used for highly effective shock value and characterization, and I could see someone wanting to tone it down.
The root issue is what's being removed: the abstract possibility of characters being called "him" or "her" independent of their appearance. To people who won't use the feature, it is literally nothing. It simply does not exist beyond a checkbox they'll scroll clean past. The game part of the game will work exactly as they expect, from start to finish.
They're whining about censorship because the real purpose of this mod is to signal that they're against anyone else having that option.
They are performatively upset by this trivial separation of character model and branch condition. Because they hate trans people. There is no other possible motivation, because this pointless change is simple and direct.
This removal is a website telling those bigoted trolls: poop in someone else's yard.
Happens all the time IRL to me. I use both he and she pronouns and ignorant people always ask why bother just pick one. Well, I did, they're my PERSONAL pronouns and I chose both these.
I'll add that my understanding is that you aren't even prompted to choose a pronoun in-game -- it defaults to one or the other based on your character creation choices, and you can then change it if you want to. It's literally a non-issue.