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.
I think most teams drop agile practices before they have knowledge to show they aren't appropriate, they usually never get used at all. They adopt what they have to because they don't really want to do it at all because they consider a large chunk of it doesn't work.
Changing the process from a position of knowledge and experience on it is one thing, doing it without that knowledge is the more usual thing and its harmful.