You can turn off push notifications for normal apps on Android, too.
But it's opt out vs opt in which is a huge difference.
Really? Huge difference? I would say about 20% (being generous with that number) of the good apps that I install try to misuse the notification. I don't find it that hard to disable the notifications for them. The benefits of notifications outweigh the spamming by a lot.
Ever tried getting a URL to some Facebook content on mobile? The only way that I've found is to "Send as Message" (Facebook for Android only implements sharing inside Facebook, there's no way to share via email or anything like that), choose myself in the contacts list, then go to Messenger, open the link in a browser, and copy the URL from there. It's infuriating.