We all have some weird sexual fantasies and preferences. If you say you don't, you'd be a liar. I had sexual fantasies about Austin Powers as a child. That could definitely be categorized as hella strange.
Oftentimes it's wrong to shame people for having different sexual preferences than you. Some people are furies, some people like omarashi, some people like picturing animated characters. It doesn't make them bad people, just a little different.
But some sexual preferences do in fact make you an incredibly f*cked up person. Some may seem bad but reveal a serious deep-rooted psychological issue. Sure, some may not be entirely your fault, but you have the choice to act on those desires or not. Having sexual fantasies about things like children, and horrible people like Nazis or KKK members does in fact make you severely messed up.
And the excuse to blame that fetish on the uniforms is complete BS. There are plenty of uniforms out there, so imagine something else. How about a uniform from a group that isn't known for brutally killing millions of people? F*ck someone dressed as a pilot or even someone in the military, just, dear god, not a Nazi uniform.