This really isnt up to debate
.
The ones that know the right answer and prefer Messi only "debate" because its honestly fun, like arguing with your 7 year old kid who is a fan of Batman about who's stronger, Batman or Superman.
The kid will always say Batman, and will make up whatever kind of crazy scenario where Batman could defeat Superman. Maybe he invents a new kryptonite weapon, maybe he builds a robot to take him on, maybe he shouts at him from the bench, who cares there is always a way.
At the end of the day, and deep inside, we all know the answer, even Batman fans. Even people from Gotham that may have the username "Gothamteo" in forums know it even if they dont admit it.