This is a big difference in viewpoint between the US and EU. The US has an undying belief in free market forces. Yet its government is beholden to those same big money forces through campaign contributions. Leading to a peculiar corporate oligarchy. We in the EU want to avoid this and keep government serving the interests of citizens.

The EU tries to balance this out with more regulation to prevent the stalemate and conflict of interests that exists in the US. Things like the Senate launch system that just exists for pork. Our welfare is for citizens, not big business :)

And it's fine, Apple doesn't have to enable sideloading in the US. But if they want to sell here they'll have to play by our rules.