I think the main issue is attribution. Especially when a lot of stuff breaks even on web, when you change the browser.
Imagine I have some PWA at home screen now, working with Safari engine. I changed my browser to Chrome, let's say it stopped working. 90% of the users will blame Apple software update instead of the Chrome choice.
Nah. Those kind of incompatibilities are rare and users will generally place the blame on their last change, more likely the Chrome install than a check for updates.
Imagine I have some PWA at home screen now, working with Safari engine. I changed my browser to Chrome, let's say it stopped working. 90% of the users will blame Apple software update instead of the Chrome choice.