And honestly, I have no problem with Apple even insisting there be an Apple IAP model (like they require "Sign in with Apple" offered alongside alternatives). Because choosing to pay the Apple tax is perfectly fine, especially if you feel it provides you benefits.
The issue is Apple's requirement that you can only use IAP, cannot offer alternative, cheaper, prices, cannot direct people to your website to sign up for things, and cannot even disclose what portion of the bill goes to Apple.
Your post proves Apple could still make money with offering it as an option for informed users. But Apple is being a bully and a thug by disallowing alternatives, and actively preventing app developers from telling people about them.
What Epic did with Fortnite should be the gold standard: Buy direct or pay through Apple. The latter providing potentially better privacy/security and user experience at a price premium.