This is all hypothetical "what if" with no real basis to back it up with. When Icardi first arrived here he scored goals outside the box, he also played with another striker and did pretty well (Palacio, Osvaldo). It's not the player who dictates the formation and tactics but the coach. If anything, the things that actually went to happen for real go against what you are saying because our first title since was won by Conte who pretty much molded the entire team, including Lautaro, in order to provide service for Lukaku.