The problem is they made Vader cool as fuck. That’s the problem of fiction in general, to portray something is inevitably to make it endearing. It’s the same thing with Starship Troopers, the satire is that the humans are fascists and we see the movie through the eyes of that society, but then Verhoeven makes money off the spin-off products like toys and funko pops that you are meant to play killing bugs with.

edit: and it’s the same problem I have with portrayals of the nazis even from purportedly anti-nazi movies. to show something is to make it endearing. History treats Hitler as some kind of anomaly of human history or humanity, as if there could not be a Hitler after Hitler. But to treat him as some kind of outsider is to remove the human component from him and in the process inevitably deify him. Even in purportedly anti-nazi movies you see this kind of deification process applied to the nazis. What happened after the war? Most nazis lost the uniform and that was it. They still live.