I think the other thing to consider here is that a comic book character can really only be as brilliant as the person writing them. And most comic book writers themselves probably aren't brilliant military strategists. So what we see on panel being labeled as brillaint might fall short by real world standards. It's not the comic book writers fault necessarily... it's not like having advnced knowledge in military combat strategy is necessarily a pre-requisite for writing comics. But the point is that we know a character is a good strategist when the book flat out says he is.
And arguably no marvel character has this written in print more than Cap. In the Secret Empire prologue for example, the narration flat out states he has the best strategist of the heroes. Doesn't mean that makes him 100% undisputably the best... but it means he's in the conversation, whether or not the characters who have written him have done a good enough job conveying that in the stories.
I'd argue in the last couple decades Cyclops writers have probably done a better job conveying Scotts leadership than Avenger writers have done with Cap (I'm a fan of Bendis, but combat was never his thing). Scott and Steve can only be as good or as bad as they are written. But the idea trying to be conveyed is that they're great at this (maybe the 2 best), whether or not that idea was sucessfully conveyed. When Steve's around, he's the guy calling the shots. If Steve for whatever reason isn't, next guy in line is probably Scott when he's doing his best Magneto impression.