Developers will package browsers in their code as a way to spy on users with fewer restrictions, not because Safari is unusable.
That being said, I returned my first and last iPhone after realizing that Firefox on iOS couldn't run the NoScript extension.
It is frankly shocking that Apple has managed to go this long while blatantly contravening the precedent set by United States v. Microsoft Corp., and I'm glad the EU is finally taking a stand on that front.