There's a half-dozen HoloJPs RTA'ing diagnosed throat/voice conditions to the point of hiatuses and literal surgery. One of them had to drop her fake voice to continue streaming.
Selen and Millie have both said this week that their voices have been shot from streaming too much and they plan to address it, and Enna had an interesting point in a recent stream that the voice isn't built to talk as long and as often as streamers try, and that tender balance is why she doesn't release covers very quickly.
So yeah, if you're streaming all the time you're going to have a higher chance of health issues: especially when you're having to be loud and 'chaotic', putting on a voice, streaming for long sessions etc to which V-Tubers do in droves.