When they exist at all. Many apps that provide important notifications (like delivery tracking, drop-off time etc) put them under the same category as marketing stuff. You can't have just the transactional tracking, you have to opt-in for the marketing notifications as well.
I had to disable from Android settings all LinkedIn notifications. I check it from time to time but I haven't missed anything, nowadays LinkedIn is mostly garbage
On iOS atleast, Live Activities are separate from Notifications. So I can still monitor food or grocery delivery even though I have turned off their notifications.
Now a few apps have started sending notifications through WhatsApp because they have my phone number. e.g. Amazon
The ridesharing apps are the most annoying about this. Yes I want to be notified when my uber driver is almost here to pick me up. No, I don't want a notification about yet another sale.