Siri doesn't speak screen when given the voice command to do so
I listen to books often and used to just give a voice command to ‘speak screen’ instead of the two finger swipe gesture. After the last couple of updates, if you ask Siri to speak screen in Kindle app, it says “ there is nothing to read here”, but if you swipe down with two fingers, it starts reading. If you make a shortcut with speak screen command, it works only in preview, but when you run the shortcut, it doesn’t work.
iPhone 13 Pro