I agree with a lot of what you wrote, but not this. PWAs are the only path for allowing open publishing of apps that is not gated by a large tech firm. While I completely understand the value proposition of app stores, there are tons of app scenarios held back by them. Two instances are small web[0] and situated software[1] as app stores keep people from publishing apps meant for small audiences by their very definition. Both of these fall under your desire to maximize the user experience.
Furthermore, PWAs are the closest thing we have to a “universal” platform. Personally, if I could write an app that worked on all mobile devices and the web in COBOL, I’d be thrilled to write “PROCEDURE DIVISION” every day.
The web is a mess because it is open. The web can be scammy because some people are scammy. Restricting PWAs doesn’t mitigate scamminess - it just restricts openness.
[0] https://ar.al/2020/08/07/what-is-the-small-web/ [1] https://www.gwern.net/docs/technology/2004-03-30-shirky-situ...