The Villain Has a Point

The Joker (obviously)

The Joker is right about human nature. You only need to study history to learn about how nasty humans can be.

Franz Sánchez

In a deleted scene, Sánchez points out that he wouldn't be in business if not for demand for his product (cocaine).

Valentine

Valentine is right about world overpopulation. Sure, his plot is pretty evil, but if world overpopulation and depleting of resources continue at the current rate, peoples will kill each other en masse anyway.

Basically the same point as in Kingsman: The Secret Service.

Stryker

Stryker may be one of the most evil characters in the X-Men franchise, but he does make a good point. Specifically - why does a school need a stealth plane?

They sure do love using this trope in the X-Men franchise! In this case, the villains are right about one thing. Professor Xavier is very dangerous and can kill simply by having a seizure.

JT

JT was certainly a sick fuck, but he was absolutely right about Ricky rescuing Joanne. Ricky rescued her from JT and she still was bitchy toward him.

Dean Wormer

Sure, Dean Wormer may be a pendejo, but it is totally understandable that he would want to keep order and crack down on the Delta House.