It's a classic walled garden, like the Android app store. You can develop Android apps that don't meet their guidelines but you can't distribute them through normal channels.
But I believe the larger issue is how it makes URL meaningless, and futures a centralisation of the web. It's not against the standard, but certainly the spirit of the web as it was supposed to be.
The part that mandates including js from a corporation on your pages.
Edit: clarified about AMP usage and Google's involvement.
Google and Micorosft (Bing) have caches. I think Twitter does to (they definitely use AMP). Lots of other social media and other platforms use and highlight AMP content, and I think there are a couple other big players with caches, too.
It's definitely not just Google.
I can’t even use the JS from a local CDN.
In this case Apple is literally helping you and publishers not get screwed. I think you need to read up on AMP, because seeing the words 'standard technologies' and 'AMP' in the same comment in that way is extremely awkward.
I'm not getting screwed by AMP, and neither, AFAICT, are publishers.
I don't like how Apple unilaterally changes the way that things work (even if that means AMP) without regard to any other parties.
They have the biggest search engine by far. They have the most popular mobile OS by far.
But it's Apple you're mad at?
You can use exactly the same arguement you made against AMP, I don't see negating AMP as some great evil.
[1] or more charitably appealing to a subset of users at high cost to a non-trivial fractions of other users
So the issue isn't that you haven't spelled out your argument in proper detail, but that you're just incorrect.
If Apple would stick to just making great hardware and products and follow the standards like other vendors do then I feel like the whole tech world would be better off.
Edit: Apparently I need to spell out in more detail my arguments because if read at surface level people only focus on AMP. This isn't about AMP. This is about sharing a link to something you are viewing. You are currently viewing the AMP page and that might look a certain way or even contain a certain type of graph that looks a certain way because it's static and fast to load. If you click Share and send this to a friend they will receive an entirely different page that might look different than what you were seeing. I don't think it's a good thing that we can no longer trust sharing a page with someone else. Now the ultimate destination is being edited behind the scenes without you knowing. It's a slippery slope that, like other things Apple has done, have possibly bad consequences in the future. The road to Hell is paved with good intentions after all.