PWA's weren't ready 2 years ago when FirefoxOS was being pushed, they're probably still not ready but there is major progress. It's mostly about scale and ecosy

PWA's weren't ready 2 years ago when FirefoxOS was being pushed, they're probably still not ready but there is major progress. It's mostly about scale and ecosystem now, development of well designed touch-friendly web components, iOS implementing Service Workers as is currently underway, and so on. That's not to say they can or will replace native apps, but there will be a growing overlap.