Earlier quoted context omitted.
On my iPhone 6s Safari AMP sites don't even work. I see the AMP header and everything below it is just blank. I always have to "Request Desktop Site" to even load the site.
Are you using an adblocker?
Too bad AMP won't work with it, but there's no way I'm disabling it as life before content blockers on iOS was hell. (Sites hijacking you to the app store, etc.)