I came across this video from 2020 that demonstrates a couple of ways it works on iOS:

https://twitter.com/Kristy_Viers/status/1287189581926981634

You can turn on the various accessibility features and try them yourselves. While I was already aware of the 'voiceover' features, I was blown away by the braille keyboard and how quickly she could type with it.

Blind people use TTS set at ridiculous speeds that make my 1.5x podcast playback seem glacial. Even back in the late 80s I remember a blind classmate who had a portable electronic typewriter thing that read her entries back to her at rapid speed.