But this is an excellent accounting methodology then: Each sub-business should run as a separate business.

It picks my interest: Companies internally run as communist economies, all resources are merged and shared, employees are not individually associated with a revenue because the group is worth more than its sum, on the outer, liberal economy. At what size / on which criteria should a group inside a company be considered an independent product-and-loss entity, in order to avoid supercorporations to make use of monopolistic behaviors? Should a 100-billion-dollars marketing operation inside Apple be allowed to function at a loss if it pumps interest in all of Apple’s other products? Can Apple Music be disguised as a marketing operation instead of as an independent entity?