The point is Apple as a platform provider made something (location without warning) on the platform available to themselves as a platform user (Airtags), that they didn't make available to other platform users who are their competitors (Tile).
One might retort "Fine, but then granting that permission once is enough." Apparently, that is only true sometimes, and only for Apple.
This is clearly Apple apps being treated differently.
The whole point of the notification is to notify you when an entity is tracking you. If you already know Apple is tracking you, then it does not make a difference if Apple's App A or App B or App C is tracking you, it is all Apple.
For me it makes no sense to make it only about the entity. It's like saying "the US government is tracking you", instead of saying "the US government is tracking you through this app right now"
Someone other than Apple tracking you, however, is notable, and so people (at least I) would always want to know if someone other than Apple is tracking me via software operating on the device.