Safari on macOS supports push notifications and it hasn't intrinsically been a bad thing -- at worst, I have to tell a web site "no, I don't want your notifications." They're opt-in rather than opt-out like native app notifications are. The higher prices you and I are paying aren't protecting us from "low-quality" notifications as it is, anyway.

At any rate, maybe you're so worried about single-page web apps being bad actors that you're happy Apple so severely hamstrings them, but I... just can't see a lot to worry about there. And if Apple let PWAs be even a little better on iOS than they are now, it would go at least some distance toward ameliorating complaints about the App Store.