In the medium/long term, this would just train people to ignore those popups. Or to use a patched browser.
There is simply no way to suppress content as long as there's enough demand. Somebody's always going to find a way to deliver. That's even true for really illegal stuff like drugs, copyright infringement or child abuse material, but so much more for content which is legal.
I was thinking specifically about PWA on Android. I don't think you can change the browser used in that case, and I could see Google decide that you cannot open a PWA if the website is on the blacklist.
There is simply no way to suppress content as long as there's enough demand. Somebody's always going to find a way to deliver. That's even true for really illegal stuff like drugs, copyright infringement or child abuse material, but so much more for content which is legal.