How much do you blame Gambit for the Mutant Massacre?

[Vegan Daddy]

You say that as if Sinister was world renowned. This is even before the X-Men knew who Sinister was and what he was about. He was scared and desperate and it made him act stupidly. And seeing as he was even then a professional thief... He wasn' completely morally bankrupt but it wasn't his strong suit. As a comic reader, you know all this information. It was given to you without having to work for it in a single book and then elaborated on several times since. At this point your just choosing to feel this way on reflex. It's a fictional character in a story that was retconed 12+ years after the fact.

Now Fantomex. There's a character to irrationally hate for reasons beyond logic.

His name is Mister Sinister and he looks like a demonic glam rocker. Gambit definitely knew what he was about and he knew about Sabretooth as well. Gambit acted selfishly out of fear and desperation and got dozens of innocent people killed.