So, if a developer takes too long developing the pre-defined micro-task which you've assigned them, you have to followup with them and report on why a micro-task took too long?
If this isn't micromanagement, what would you define as micromanagement?
Except at most companies that use Scrum, there are very rigid rules sent down from above regarding the implementation of Scrum. These rules apply to the whole company and can't be questioned or changed via retros.
In Agile, as implemented at most non-consulting shop places, the Product Owner really doesn't have the authority to block things coming into the sprint being pushed from executive staff, important customers, or sales. The PO just acts as a point of contact/funnel to push the stuff coming in from these places into the sprint.
Just search on "dev manager" and agile. You'll come across lots of articles from scrum proponents that attempt to severely downplay the need and role of dev managers and sometimes claim they aren't needed at all in an agile shop.
The one thing they usually don't mention is all the new agile servant leader positions your company will have to hire instead of dev managers.
Uh, your friend did not invent that nickname. It has been around for more than a decade and is used commonly including in media articles about Whole Foods.