AI TTS has been available for quite some time. Tacotron V1 is about 8 years old. I don't think we saw much bottom end replacement.

IMGO(gut opinion), generative AI is a consumption aid, like a strong antacid. It lets us be done with $content quicker, for content = {book, art, noisy_email, coding_task}. There's obvious preconceptions forming among us all from "generative" nomenclature, but lots of surviving usages are rather reductive in relevant useful manners.