10 Ways The MCU Was Almost Unrecognizable
2. No Civil War
In addition to having "old-fashioned" beliefs (which is an extremely polite way of putting it), Perlmutter was/is notoriously frugal, always looking to pinch pennies where he could. That almost derailed Civil War.
Downey wanted a large paycheck for Civil War, and when Perlmutter found out, he went over Feige's head and tried to have Downey written out of the film. Disney heard about this, and quickly forced Perlmutter out.
Had they not done this, Civil War would have instead focused on Zemo unleashing the Madbomb, which would have turned civilians into crazed berserkers, almost like zombies. Sure, we would've gotten more Zemo, and we still would've gotten the Cap/Bucky stuff, but without it?
Civil War featured a LOT of setup. Not only did it introduce Spider-Man, Black Panther, and Zemo (who will feature in The Falcon and the Winter Soldier), but it laid the groundwork for the Avengers to get wrecked by Thanos.
Without Civil War, they would've been together to fight Thanos. They may not have won, but they wouldn't have gotten so thoroughly destroyed. Without that, there would've have been no triumphant reunion in Endgame.
Not only that, but Feige almost quit over the whole ordeal. Where would the MCU be without Feige?