correct me but those features are denied by apple and mozilla for very good reasons (privacy and security) besides beeing anything but 'basic' (midi anyone?)
PWA's do work, but they are hard to install (not available in the appstore, the user has to go through a non-obvious sequence of steps they won't discover unless they Google it). They are slow (because safari refuses to implement caching of compiled JavaScript or webassembly). They can't store persistent data, so the user experience is terrible (yay - who wants a notekeeping app that deletes all your notes every 30 days?). The data doesn't sync to iCloud. It doesn't integrate with the rest of the OS (no way to share a picture to a PWA for example). The Safari browser engine they must run in is ~3 years behind desktop and Android browsers with supporting web standards. There is no way to do background stuff like playing music, using the GPS for directions, etc.
If you're scared of something, sometimes it's best to invent it and then not invest in it than to let someone else invent it and do a decent job of it.
Classic example: Oil companies "investing" in clean tech in the 90's, sucking up government grants and public attention and never really getting anywhere probably slowed down the switch to renewables by 10+ years.
The thing holding them back is apples deliberate crippling of them to make them hard to install, slow, buggy, and not having basic platform features.
I believe Apple is deliberately doing that because if they supported PWA's properly, they'd loose all vendor lock in.