Forcing the rendering engine upon a browser manufacturer is just "cost of doing business" on iOS. It does not have as negative consequences as forcing an entire browser upon a user (like Microsoft is doing). Chrome on iOS can still do pretty much everything it wants, including telemetry, sync etc. The users are ensured to get a browser with a rendering engine that is carefully optimized for performance and battery life by the phone manufacturer, so I'd argue the user is actually better off.