People installing what they like on their devices doesn’t change how your device works
What I'm more concerned about is Apple being forced to allow non-WebKit browsers in the App Store.
Apple requiring the use of WebKit on iOS is the only thing stopping Chrome from having a complete monopoly, aside from Firefox with its 5% marketshare.
I don't agree that forcing WebKit on iOS is the solution, however. The law should seek to break Chrome's monopoly, not enforce another.