Yes, so if Apple were divided into separate hardware and software companies, then a third company X could order both these companies to come up with hardware and software solutions, and reach the same result. In this case, what you call management would be performed by the third company.
This is imho a better way of building things than having everything completely integrated in a single company. A fourth company could do the same thing as X and build an alternative iPod. And so could a fifth, etc.
> Wouldn't you agree that it is better if all companies have equal access to TSMC's services?
It’s certainly debatable, which is why we have antitrust regulations.
In the specific case you suggest of separate software and hardware companies, the reason that Apple has succeeded where others have failed (in large part) is because of their vertical integration. To wit: the equivalent of Apple (ignoring communication overhead, which is also huge) would be software and hardware companies that Apple has an exclusive contract with, who spend all of their time working on what Apple asks them to.
When they start serving other customers, their operational overhead increases, because they have to figure out how to schedule production schedules fairly across multiple contracts, and probably start to divide up their production functions by product area and customer.
They also typically end up having to make concessions to multiple customers, and risk ending up at a lowest-common-denominator product that fits the limitations of other customers more than it fits Apple’s specific set of capabilities and limitations. This is the market effect that drives standardization: agreeing on the lowest-common-denominator for everyone before production and product development starts.
In sum: they become less good at delivering specifically what Apple needs, whenever Apple needs it.
Why don't we remove all firm advantages completely and have a fully open playing field? Ban companies entirely, everyone is a free agent! Everything shall be an arms-length transaction with lawyers at every step.
This is imho a better way of building things than having everything completely integrated in a single company. A fourth company could do the same thing as X and build an alternative iPod. And so could a fifth, etc.