Ok i study language, i also study cross-linguistic pronoun systems as part of my job, this is really really odd. I’m not sure when specifying multiple pronouns began to equal ‘you should switch between these in turn within an individual speech situation’ (within, literally, the last year? Because I did a Google Scholar search for linguistic studies and came up completely blank) but…who came up with this? Are you sure???
I recognise (as, technically, a working linguist) that language is flexible and open to innovation, regardless of the political beliefs of others observing the innovations (so I’m not pro-neopronouns or pro-singular they, but I accept that people are using them and it’s something that should evolve naturally). But i’ve never seen something so counter-intuitive to the way language, in general, actually like….works….
the point of pronouns is that they’re anaphoric, and that they can be used consistently to refer to a consistent referent (this is pretty much the same cross-linguistically: although some systems code for honorific and deictic functions, allowing for different pronouns depending on who the speaker is or who the listener is, it is absolutely missing the point of pronouns to have variation within a sentence with the same speaker and same referent).
But the bigger issue: you are requesting some degree of arbitrary variation in pronouns from those speaking about you, as a mark of respect (or kindness)
So a) syntactic systems are not arbitrary - grammars are rule-based, and based on repeated structures which are familiar to everyone in your speech community. Systems like pronouns - even neopronouns - must have shared, identified and consistent usage patterns if they are to be considered part of a language’s grammar. This is why you’ll find codified tables for pronoun systems in every language that has pronouns:
The table above is from Latin, which I picked because its pronoun system does have the occasional added function of signalling politeness and respect towards the referent (person being referred to). In (at least the written, classical version of) Latin, you can use the plural pronoun to show that you respect your singular human referent and that you recognise their higher status in your present situation (job-wise, age-wise, slave or freedman etc.)
I don’t think this is that different from your plea that people alternate pronouns - because the alternations are meant to indicate respect (for the referent’s gender identity) and politeness. But there are several reasons why I also don’t think alternating pronouns will ever become an accepted, agreed-upon act in English (or any language’s) grammar:
You can’t codify it into a widespread rule. The (simplified) rule in Latin is ‘if, according to the structures of ancient Roman society, you owe respect to the referent, use ‘vos’, if you don’t, use ‘tu’’. This is a learnable rule. It is possible for others in contact with you to learn it from exposure, to remember it, and to draw on it without thinking. There are many other languages around the world with honorific pronoun systems, proving that this kind of rule can evolve naturally and be adopted with minimal speaker effort.
Your proposed rule in English = ‘if someone specifies multiple pronouns, then alternate between them’. This leaves so many questions unanswered, and so many issues! Are you supposed to select the pronouns randomly? Arbitrarily? Because there is no grammatical system (like, in the world) where randomness or arbitrariness are factors syntactic rules - basically by definition! Do you select the pronouns in a special pattern (there’s also no language where this happens) - and if so, which pattern, and which pronoun comes first, and what are the implications, and how are speakers supposed to learn this? Are there any particular intervals within a sentence or speech act where you should change the pronoun? Because there is also no grammatical system where this factors into rules of usage! What if you have multiple people in a conversation, all mentioning the same referent - what do you do? How do you cooperate?
Basically it’s unreasonable to expect people to vary pronouns within a sentence as a mark of respect, not even because of your gender identity but just because it is fundamentally not how language works. This is also ignoring a ton of info about speaker effort and language processing lol. You can codify neopronouns (these are actual rules that, given a few years, people might be equipped to put into use if willing):
But you cannot codify random variation to the extent where it becomes a syntactic rule!!