> PWAs would be cheaper to develop overall than building 2-3 separate code bases.

But that's my point: that's exactly the promise of every single cross-platform system out there. But in my experience, that's generally not true for non-trivial apps (ever heard "write once, debug everywhere"?). And second, it usually makes for worse UX on all platforms.

I feel like many people consider PWAs as a totally new thing, but at the end of the day, it's a cross-platform system. There are tons of those; just look around, cross-platform is not a silver bullet.