So if price pressure from consumers forces down your profit then you should be allowed to exploit a monopolistic position to leverage profits in another sector?
Like, own all cinemas in a country but home-viewing keeps profit low, so now it's fine to only allow people to visit your cinemas if they buy clothes from your clothing company?
A better example would be you own 75%+ of the cinemas but revenue wise you only control 50% of it. And in that case I think it's fair to do it. If they would force Apple out that would be a problem, but instead they even give you the basis for your own cinema for free (in contrast to Apple).
Like, own all cinemas in a country but home-viewing keeps profit low, so now it's fine to only allow people to visit your cinemas if they buy clothes from your clothing company?