> Pretty sure there's enough blind people who don't listen to voice at insane speeds, because they listen in their non-native second language or for whatever other reason.

Yes, for lots of reasons. It takes practice to get up to a high speed with a given TTS. People who go blind later in life are just beginning, and it can take a long time for them to get up to really high speeds. You may also need to reset somewhat when you change from one TTS to another. And blind people's ears are subject to problems just like anyone else's; if your hearing isn't great you may need slower speeds or higher volumes or both. That's why even though most people use screenreaders at much higher speeds, the defaults when you turn on a new device are painfully slow. You have to set a conservative default so people with less experience/worse ears/whatever can get by.

Anyway I don't think it's a criticism. It's just noting that it doesn't depict how most people will use end up using it, and if you're curious about what typical usage sounds like, you should look for another example.