these are not inherent problems to PWAs tho. The data loss situation is pretty much the same for any native app. They can choose to be local only or sync to a server. Apple can also support iCloud for PWAs in theory.
Also there is nothing stopping extensions to work for PWAs. They do on Chrome desktop and you can disable/enable extensions per app. Not an Android user (yet) so I don't know how is it on mobile.
Also there is nothing stopping extensions to work for PWAs. They do on Chrome desktop and you can disable/enable extensions per app. Not an Android user (yet) so I don't know how is it on mobile.