No, that’s not a correct comparison. Consumers don’t buy a device from Epic in order to run Unreal engine games. Consumers don’t care at all what engine a game runs on, they only care about the game itself (and what platform it’s available on).

If you forgo the iOS platform, you lose out on the vast majority of mobile app revenue. Android may have greater market share than Apple but iOS dominates the market among people who actually buy apps (mostly affluent people in western countries).