Great military battles are won by leaders who have sufficient committment, strength of will, and self-confidence that they can get the troops to fight for them. Some degree of military prowess helps, too. Absence of jerk-dom and pomposity aren't included in the list of attributes.
Most of history's great military leaders were loud, rude, or pompous jerks, and many were masters of internal politics. Dugout Doug fit the mold.
I did not say that the presence or absence of such is a qualification or lack therof.
It is my opinion that Macarthur's prowess was way overblown by his own image projection machinations, and that the general impression of his tactical genius was a product of him, his benefactors and his staff. (Inchon was brilliantly done, that I give him credit for, but the dummy couldn't keep his mouth shut in Korea. He could not accept that, for better or worse, the military is controlled by elected officials, not the other way around. He began to think he had the same power over the use he wielded over Japan after the war. Not so smart)
Patton was even more rude, arrogant and (sometimes) pompous, but he had the advantage of producing results.