FYI Steam doesn't even have content restrictions on the marketplace now. There's a ton of adult games on there now. So not the best point.
The point is there are always going to be limits to what you can release on any platform. Does that count as creative control over developers?
If there truly are no restrictions on what you can publish on Steam, then my initial list of examples is wrong, but that still doesn't make Apple the sole company with restrictions for their platform.