Use of AMP or PWA Should Be Determined By The Needs of the Website
When deciding between implementing AMP or a PWA for your site, John recommends choosing the one most suited to your needs. For example, PWAs will be useful for websites providing interactive elements and offline accessibility, whereas AMP is great for publishing content.
A PWA is a Bigger Investment than AMP as a Solution for Improving Mobile Usability
AMP can be easily implemented if you have a modern CMS plugin to convert your pages. PWA implementation requires a lot of development work, largely based on complex JavaScript, to redesign a site. If both are too much work, focus on improving a responsive version of your site instead.
Make Sure A Separate PWA is Canonicalised to Your Mobile Site
Google won’t get confused between your main site and separate PWA as long as you have canonicalization in place.
PWAs Are Treated Like Other JavaScript-Based Sites by Google
Google doesn’t have a special set of requirements for PWAs, they are treated the same as any other JavaScript-based site.
John Suggests Considering a PW-AMP Set up – a PWA Combined With AMP Content
Google have been looking into a PW-AMP set up, combining a PWA with AMP content. John suggests this combination is something worth looking into.