How do you think Gmail writes the content out onto the page? Goodness gracious, they have to store it and process it!

I don't really see how running the contents through an quick reply generation function is different to running it through whatever function prepares the body for display, here. An implementation of that which involves wide-scale mining of email content is imaginable, but not necessary.

> Smart Reply uses neural networks to figure out the main intent of an email, and then suggest short and adequate responses. It’s an incredibly useful feature, it works surprisingly well — and it clearly requires for Google’s computers to “read” your email.

Would you stop using Protonmail if they offered the same feature?

I'm not sure who you are addressing, but I would stop using ProtonMail if they did. Then again, I've never found Google's response suggestions to be useful.

So now they only mine it for things that are good for the user experience?

I'm sure that is the orginal intent but can quickly morph.