Are there guidelines on the timing and frequency of notifications?

I'm noticing an increase in the number of app notifications that seek a more continuous engagement threshold. Then, I get notifications about almost anything, at least once per hour.

The extreme example is Facebook, which lately is using false notifications. An example: right now, I received a message that said something like "20 people saw your story before it disappeared, see who were the ones who saw it". Which is really strange because the stories last 24 hours and I have not used Facebook for at least 10 days. Of course, I clicked and I did not see what Facebook said, it just took me to the main page.

In addition to this extreme example, I receive notifications from groups every 30 minutes, until I interact with the group. The worst thing is that my only option is: receive all notifications or none.

But this is not only limited to Facebook. Although Facebook is taking it to an extreme, I am seeing it in many applications, often with notifications that are trivial and absolutely unnecessary, sometimes false, often simply "click bait".

I was asking myself more and more about this and could not find anything conclusive about it. Personally, I think that these behaviors vary between "dark patterns" and "anti patterns", but I do not find definitive information regarding the proper frequency of notifications (obviously when there is an important event for the app or the user, but I refer more to these generic notifications that only seem to find engagement, which does not seem bad to me per se, but I think there should be some guidelines on the frequency and excess of notifications).

In short: are there guidelines or studies on thresholds to declare a notification strategy as legit and appropriate, or a dark pattern, or an anti pattern?