"New business terms available for apps in the EU — to reflect the DMA’s requirements for alternative distribution and payment processing, Apple is also sharing new business terms for apps in the EU. Developers have a choice to remain on Apple’s existing terms or adopt new terms that reflect the new capabilities."
So this is essentially Apple making the alternative so unappealing that no-one will switch and status quo is preserved.
Apparently, once you sell in a non-Apple app store - you can't go back. Not just for the app in question; You, as a developer, can never sell in an Apple EU App Store ever again. Not even unrelated apps.
Still appealing?
"Developers who adopt the new business terms at any time will not be able to switch back to Apple’s existing business terms for their EU apps."
"New business terms available for apps in the EU — to reflect the DMA’s requirements for alternative distribution and payment processing, Apple is also sharing new business terms for apps in the EU. Developers have a choice to remain on Apple’s existing terms or adopt new terms that reflect the new capabilities."
So this is essentially Apple making the alternative so unappealing that no-one will switch and status quo is preserved.