I don't see why the Microsoft case is all that relevant; it's not like Microsoft is the archetypal definition of monopoly behavior in hardware/software, and only companies that do things the Microsoft way should be punished.

I personally don't think the distinction you point out should actually be important at all. The end result is an anti-competitive platform, and that's all that should matter.

If we go by the oft-used test of consumer harm, consumers get harmed in exactly the same way on both platforms, with higher prices (due to percentage fees that you can't opt out of) than if the market were more open.