Looks like Google have recently added a means of getting out of the AMP "jail" and arriving at the original source site by clicking a little link icon in that irritating header that constantly pops over content while scrolling.
This is very welcome. My biggest gripe with AMP was that there was no way out of it.
Too little for me. I still can't easily copy that URL, and there's no way to opt out of it. Instead of fixing their complete break to the way with the web works, they put in a little tiny patch and clean it's just as good.
You can now (although that's still different from any other site). I'm pretty sure that was only added a few months ago and when it was first released you couldn't easily copy the URL.
This is very welcome. My biggest gripe with AMP was that there was no way out of it.