I would say Netflix and Spotify are literally selling content, which they are spending billions to develop or license. If Apple's APIs were available as an optional service that cost 30% of an app's revenue, I'd expect two things to happen: 1) large companies would build apps from scratch for much less than the billions Apple's APIs would cost them, 2) open source frameworks would fill much of the void. We can't know how much Apple's tools are actually worth when the iOS ecosystem requires that you pay for them.
Your argument seems to be that Apple's customers should be able to pick and choose which services in the bundle they pay for, even though they use all of the services, yet might not if they weren't paying for it?
Netflix, Spotify, et al are obviously making very good use out of Apple's efforts. Otherwise why don't they do exactly what you propose? Why doesn't a company like Epic do it? They would LOVE to achieve what you're saying seems so easy, and then stand up and shout how much they're being abused. But Epic chooses to use the Apple engineering efforts and STILL cry abuse. ?
If a company chose to roll its own solutions it would cost a decent chunk of the fees Apple is charging for those apis/frameworks (for now we're going to ignore the OTHER benefits in the 'bundle' they get).
And it would 100% result in a reduced quality of user experience for their customers.
And it would cost MASSIVE amounts of time. Where customers would be irate at the lack of features that all the other apps have. And this isn't even to mention the thousand 'little' (but crazy-hard to roll your own) region/language/accessibility/etc specific features that would probably never come.
Plus the overhead. Stupid amounts of office-space, administration, etc if they hired in. And even if you figured they could contract out this work out (assuming there were companies out there who could magically take on the capacity of all these megacorps ditching Apple, but asking for a complete iOS parity experience), there'd still be a stupid amount of overhead lost to defining requirements and agreements. Plus the absurd markup they'd have to pay, bringing the costs ludicrously higher than you're assuming is the cost to merely code the stuff that brings parity.
Like, I don't think you understand that it's simply not possible to achieve what you seem to think would happen. Open-source frameworks? That DON'T make heavy use of Apple APIs?? You don't understand the industry.
Show me ONE app that makes zero use of Apple's apis/frameworks after the app is launched (ie, a completely blank slate after being downloaded and launched), and only THEN can you talk about how easy it is.
So far though, nobody has done it, because it costs too much (in time, money, and customer experience) to not sell Apple's development efforts.
