Google created it to consolidate control of content on their platform to get people to get used to a specific UI provided by Google. There are other companies that hold caches, but the design and implementation is essentially chosen by Google (note that the fact that the AMP privacy policy just leads to the Google privacy policy). I can completely understand why Apple would want to get rid of it -- it adds a Google UI to the article that otherwise wouldn't have it and it isn't necessary to see the content.

Edit: clarified about AMP usage and Google's involvement.