Managing administrators in both Global Admin Console and Admin Console it is just a pain.
We can sync groups and you have the false impression that you can use the everywhere, where for Admins they have to be added manually in a list in the UI.

I understand from your support that there are different layers of admins for product, but having separate groups for all or them it's also an option.

I'm not sure about other companies, but for the ones that just have a couple of people responsible for licenses and Adobe management they have all the admin rights everywhere.
Making sure to provide an easy way to configure certain settings once so you don't have to worry about using the UI to actually grant permission is a huge improvement.