No they wouldn't.
They already pulled Rocket League from the steam store[1] after purchasing their developer. There is no reason they would treat ios any different
Steam developer agreement forbids such practice. You can't set base price of your game any higher than in other stores. And, to be fair, situation isn't as dire as you described it, you can still download and play Rocket League with the latest update in Steam if you have it on your account.
terafo|4 years ago