I absolutely agree that people should be able to choose how they use pronouns (or in fact any component of language). Communication is a mutual endeavour, and

I absolutely agree that people should be able to choose how they use pronouns (or in fact any component of language). Communication is a mutual endeavour, and I will always make my best good-faith effort to understand what an interlocutor is trying to convey (assuming I want to talk to them in the first place :), even if they choose to use language differently from the way I would. In fact (within reason) I will even adapt my own usage in some cases - e.g. I will do my best to use the pronoun "they" (or "xe" or "foobar" or whatever) when referring to someone who wishes to be referred to in that way, even though (despite knowing several languages with gender-neutral pronouns) I find that takes non-insignificant mental effort when I speak English. That said, precisely because communication is a mutual endeavour, and language is a coöperative framework, there is no guarantee that -- just because you choose to use "they" in this way -- others will follow. I wouldn't be terribly surprised if, within a generation, "they" became an unmarked definite gender-neutral pronoun in English (today it is arguably unmarked in the case of an indefinite antecedent, but extremely marked otherwise). But I wouldn't be terribly surprised if it didn't, either. Language change is an emergent process and not something that can easily be forced in either conservative or radical directions.