The issue here is that the abuse of push notifications makes push notifications borderline worthless. That's why I don't allow them at all on my machines. The value they provide is swamped out by the abuse of them.
It's easier to just disable them all by default, really, then I don't have to bother with micromanaging on an app-by-app basis. This is particularly true given that the majority of push notifications are spam.
I wasn't talking about OS defaults. I was talking about my personal use of my machines. I don't allow any push notifications by default because the benefit of them is tiny compared to the hassle of dealing with them.