It's necessary in some things, for example I made an app for myself where I have words/sentences spoken by text to speech, something like 12000 words/sentences, both in a normal speed and a slow speaking speed. That would be very difficult for me to do with natural voices as that would require some human to read these words/sentences, not to mention how expensive it would be, when I was able to do it for free with AI.

There are some things where AI voices absolutely ruin it, but it's not always a requirement for "emotions" to be felt in the speech we're listening to.