I'm not sure I see your point
Apple music = Amazon music = DRM free
Apple iBooks = Amazon Kindle books = incl DRM
Apple movies = Netflix = everyone else = incl DRM
Correct.
Less correct. Kindle and Netflix have DRM, but they don't have the platform lock-in of iBooks and movies. iBooks, as far as I know, is only available on iOS. DRM is bad, but DRM that's tied to a smaller range of platforms is even worse.
I'm not sure I see your point
Apple music = Amazon music = DRM free
Apple iBooks = Amazon Kindle books = incl DRM
Apple movies = Netflix = everyone else = incl DRM