emphasis added on and/or; it seems like Apple is being forced to break down fees according roughly to their costs (?). Maybe installs from altapp stores cost them some resources because they want to verify the notarization each time?

Companies do these kind of trickeries all the time. That's how they avoid paying taxes: by technically being within their rights. It doesn't matter if everyone knows what they are doing.

Apple's EU HQ is in Ireland and its totally selling the product from there, German companies are definitely don't sell restricted parts to Russia, they are selling it to Kazakhstan and Kazakstan suddenly had success with selling stuff to Russia, all the SV startups are incorporated in Delaware, all the Ships are Panaman and all kind of products that are assembled just the right way to avoid ban or taxes but can be reconfigured to do the banned thing.

Even at this very topic, Apple is trying to comply in such a way to circumvent actually allowing to freely install apps to iPhones.

So before the cost was $99 for 100% of users, and now it is $99 for 99.9999% of users, and a higher amount for a tiny, tiny, tiny fraction.

This is only adding new alternative choices, not changing or removing any current systems and methods and prices.