I didn’t claim that they/them was used just to keep the subject’s gender neutral, but that it was used for individuals in a way that did so (whether intentional or not). As of only about 700 years ago. Yes, it usually meant more “any given person” than “this specific person”, but that’s a tiny leap to make in such a long time, and the grammar takes the same form either way. Specifically for those who are non-binary, they/them is attested from the 20th century onwards, which is awesome. It’s at least a decade or so older than I’d thought!
Using he/him as a gender neutral pronoun is generally seen as archaic in modern English, in large part because it enforces sexist ideologies and assumptions. Even without considering genderqueer identities, I strongly recommend against using it that way.
A request isn’t pushing things onto anyone. If it were, it wouldn’t be a request.
In more pragmatic terms, requesting specific pronouns is a way of advocating for equal treatment. There is nothing entitled about asking for the same recognition that cisgender people already receive.
Using he/him and she/her for entirely cis people is also thinking about gender, after all. We’re just so used to these that they require less conscious effort.
I agree with your comment that “grammar does not define your gender, it’s the other way round”, in that the way we were using English before was insufficient to describe the vastness of how people experience gender, and we are finding ways to improve language to better understand each other. It’s great!
As for clarity, again, pronouns don’t exist in a vacuum. In all writing and speech, information tends to be included as and when desired. To be blunt, nobody owes you a description of numbers or masculinity/femininity/neutrality. If you’re really unsure, you can ask.
Language can’t be disentangled from respect and recognition. This has always been the case. It is a fundamentally human tool, not a machine.
If you’re determined to treat it as one, though, maybe oil your machine with appropriate doses of capital letters.
As for how important/non-important it is to focus on gender: on an individual level, that’s not something for you to decide, except for yourself. But it does make me question why you would choose disrespect on the basis of obsolete grammar here instead of finding a space where we can help each other address other issues in constructive ways.
Regardless, seeing as gender is a huge part of human identity, society and the roles we find ourselves in (not to mention whether or not we’re safe in those spaces), taking time to discuss it and consider it is absolutely necessary and not something to be condemned.
P.S. Yikes! Sorry to anyone reading that this got so long. Can you believe I did a lot of editing to make it shorter?