Would it have had to be more locked-down? I think letting the web be a first-class citizen would have been enough; economic incentives would have taken care of

Would it have had to be more locked-down? I think letting the web be a first-class citizen would have been enough; economic incentives would have taken care of the rest, because few companies want dramatically more paid devs on staff (for iOS, Android, BBOS10, Windows Mobile, etc) for a marginally better experience "Just throw out a PWA" would have been enough for most execs to get behind, IMO, especially in the early days when who knows which platforms will stick around and have been worth developing for in the first place.