To be fair, not even Firefox (desktop) can be bothered to support PWA.
PWA is, as an honest assessment, dead. It was a neat idea - kind of like BeOS or Amiga - but it's dead.
My personal take is this is because PWA had too little to define itself to the everyday Joe with. The appeal of PWA was primarily to developers - because then they wouldn't need to build apps or pay fees. What appeals to developers though, doesn't have any intrinsic appeal to Joe.