I mean, it's far more than that. Most importantly:
>Historically they have been held to include exclusive dealing, price discrimination, refusing to supply an essential facility, product tying and predatory pricing.
While IANAL - even as a plebe I can pretty easily tie refusing to allow third party app stores to both refusing to supply an essential facility, and product tying.
Why should my choice of hardware or OS dictate the apps I'm allowed to install? That's 100% product tying. It would be one thing if third parties just had no interest in supplying an alternative app store. It's another thing entirely to lock them out via your monopoly on the ecosystem.