Actually no it’s not.
Apps can be side loaded for free bypassing the app store.
With the App Store, apple is providing a service.
Oh come on. While technically true, in reality this only applies to specific scenarios, ie: custom apps for business. Consumers have no choice but to use the App Store for software and developers have no way to reach iPhone users unless they go through the App Store.
I think the government will eventually take action when it comes to the App Store. The fact that Windows users could download and install another browser didn't stop the government from making a case against Microsoft. The fact that consumers can choose Android over Apple probably won't matter in the end.
I have mixed feelings when it comes to the App Store (as a consumer). The simplicity is great, but I don't really care for Apple's nanny approach to what it permits in the store, making judgements, moral and otherwise, about what its customers should be allowed to access. Even though Apple is a reasonably benevolent gatekeeper, I don't like the concept of gatekeepers in general. I loathe the day the Mac App Store is the only way we'll be able to get Mac apps.
Also, given the number of privacy-related issues with certain apps in recent years, I'm not convinced that Apple does a very good job of vetting the apps it approves.
If I were a developer, I'm not sure how I'd feel about the 30% cut. On the one hand, Apple's solution is elegant and they'd handle all of the tedious details like hosting, payment processing, etc, things I'd have to pay for myself otherwise. So I see the appeal. However, I have no choice. And neither do consumers. If my app doesn't meet Apple's "standards", consumers will never get to use it and decide for themselves if they want it. Apple has already made the decision for them. And if I want to host my own site, sell my software directly, and create a relationship with my customer --- like I can do today on macOS --- that's not possible. To me this is inherently problematic and it's only a matter of time before some government (US or otherwise) steps in and forces some changes.