>Note that many recording artists do not actually make that choice; it happens further up the chain.
If they don't make such choices for themselves, they're not much of an artist, more like mass-produced manufactured candy pop/r&b/etc...
"if you're leaving artistic choices in the hands of someone else and aren't building your computer, DAW, and semi-conductors from scratch, all on your own, you're not much of an artist"
This is some novel kind of cross between a strawman and a slippery slope fallacy, so full of bad faith that it isn't really worth an answer...
Because of course there can't be a cutoff point, with my argument applying to the level of involvement I described (if one's vocals are to be processed with autotune or some major effect is a major thing for a vocalist to leave to others, even level of reverb or echo will often be a thing to debate with the producer/engineers) and not to ridiculous meta-levels like building your own DAW.
Note that many recording artists do not actually make that choice; it happens further up the chain. Regardless, whether or not a singer or producer uses a particular effect on their voice does not distinguish between the vocals being 'real' or not. If you simply don't like the way it sounds, on the level of artistic taste, well, you can make that judgement for yourself, but, to claim it's more profound than that is just pure pretense.
Also, why are we talking about autotuned vocals on a thread about a speech synthesizer? Claims of 'real vocals' are already out the window at that point.