Really can't agree more.
It's clear that the App Store offers significant value for many vendors, and charging for it is fine. Epic apparently generates $500m of revenue per year from the iPhone, and they're doing so using platforms, tools, and APIs that Apple built to help developers do that. It's reasonable that Apple would get a slice of that. The company I work for makes, well, a lot less revenue that Epic, but a decent chunk of the revenue we do make goes to AWS and Stripe, as compensation for their help in letting us earn that revenue.
What's not great is the specific way Apple has chosen to get this cut. AWS and Stripe both run, more-or-less, on a cost-plus model; they package up a service, and resell it to us at a markup (in the case of AWS bandwidth, a very, very, fat markup), and they let us decide how much of that service to consume, and how we want to balance our purchases between them and competing vendors.
Apple's stance here is a little like if AWS tried to force people who use any AWS service to use their overpriced egress bandwidth for everything, and sued customers found to be using Cloudflare to reduce their costs.