AMP is not supposed to necessarily replace existing pages, but can rather be created by publishers as lightweight/performant alternatives for mobile visitors ar

AMP is not supposed to necessarily replace existing pages, but can rather be created by publishers as lightweight/performant alternatives for mobile visitors arriving via Google Search. Hence why you can declare <link rel="amphtml" href="/yourampversionofpage" /> in the normal page. Those with JavaScript switched off probably won't be suggested the AMP pages in Google Mobile SERP. So you could serve the JS-optional pages to all clients, progressively enhance for JavaScript users and offer AMP pages to mobile JavaScript users.