Apple didn't sponsor the DMA, it was fighting tooth and nail against it. In general, EU politicians are harder to buy because they are more fragmented, and bribery is still illegal BTW.
That said, on the one hand, this fee structure is actually illegal under the DMA, the "core platform fee" nonsense is specifically illegal, and the EU is already on their ass about it.
On the other hand, this is just as if MSFT made Internet Explorer super expensive to license after they got hit by the same kind of regulation way back when. This just means that if you are an iOS app dev, you might want to release on something other than the App Store. I expect Google Play being available on iPhones pretty fast for example, or the Windows Store, or a bunch of other third party stores, and Apple can't even preinstall or prefer the App Store on iOS over them. All the App Store being more expensive will do is make App Store fade to irrelevancy in the long run.
There is one aspect people don't really talk about yet, because it is not just about "allowing sideloading". The law says "no self-preferencing". That means that installing an app from for example F-Droid has to take the exact same amount of taps with the exact same UX as installing something from Google Play. Same goes for the App Store. The point is not to allow sideloading, but to erase the word sideloading from the vocabulary of the platform and make it just like Windows in that regard.
This is not just bringing iOS to where Android is, Android is still not compliant yet either. Neither is Windows by the way, because of how they treat Edge.