i hope that the ghost of ol' wild billy shakes* greets every single person who says "they is singular" in the afterlife and immediately challenges them to a no-holds-barred beatdown
*william shakespeare
i feel like all of the people who view the english language as immutable and get really stick-up-their-ass about it also are likely to hold shakespeare in the greatest of esteem
which is ironic, because shakespeare is very clearly of the opposite opinion wrt mutability of the english language
i mean he gave us newfangled terms like 'eyeball'. and 'newfangled'.
even if the claims that shakespeare invented these words are drastically overstated, he still was the first person to use many of these in literature that survives. so even giving wild bill shakes as little influence as possible, he was still making the conscious choice to include words that hadn't made it into common use of written english yet. (in other words, it's probable he was 'canonizing' terms invented by/used by lower classes into the realm of the upper-class.)
ultimately, if it's good enough for wild bill shakes, and if it's commonly used and understood by modern writers, it's good enough for me.
and if you see anyone kvetching about it, dear fediverse, make relentless fun of them. "oh you're too good for Shakespeare now are you? going to mark up Hamlet for being ungrammatical?"
stay tuned for more of my """""utterly daring"""""" english major opinions that include shit like "a split infinitive is fine actually"
and what always gets me about these stick-up-their-own-ass types is that even if they go purely with the idea that the english language is immutable and we must not change it in modernity... they're always hoist by their own petard. https://nyulocal.com/shakespeare-used-the-singular-they-and-so-should-you-6452240ca9e0
of course i'd love it if the english language had an elegant third person singular neutral pronoun, but english ain't latin. and we have been using 'they' in this role for centuries.