Ok so I guess Android has some sort of API for allowing an app to install additional icons on the desktop with specific parameters like a shortcut and it shows the icon with a little icon representing the parent app, makes sense.

So if you install a PWA from Firefox it runs in Firefox and from Chrome it runs in Chrome similar to desktops. Looking at it this way I could see Apple doing something similar with less effort than trying to standardize a web view API and have PWA use the "system default browser".