Gaming consoles.

We can still buy games outside the platform at this point. But we're probably nearing an age of consoles without disk drives, then yeah.

I guess there is still the in-app purchase angle.

Strictly speaking, retail games are also part of the same platform. Game consoles have the same lockout policies Apple does - in fact, they were literally invented decades prior to the iPhone by console manufacturers. You still have to pay a platform royalty on physical copies; except now you also have to throw margin to distributors and retailers, too; and the games can be resold without you making a penny.