I’m not an App Store seller so I have no idea what this means. You can’t just pick any number that you want to sell your app for? You have predetermined prices set by Apple?
Correct, Apple requires you to use one of it's artisanal price points, hand-selected from a only the most psychologically supple increments.
Yep. And previously you couldn't choose a non-zero price lower than $0.99, so the new price choices will probably go to use.
Correct, only pre-approved price points are allowed.
As I mentioned above pretty sure this was a limitation of their SAP based system and the way it was integrated with the iTunes Store (what App Store used) that required you to pre-define price points.
It works in tiers. You can set the price point to be tier 1, 2, 3, 4 and so on, with tier 1 being $0.99, or whatever the lowest price point is in all the other countries that the AppStore is in