I believe people show heir true self when tested. Trial tends to break the surface.

I get what you're saying, but I think it's abit inaccurate to say that pushing people's buttons reveals their true natures because it presupposes that everyone is inherently "bad", when really there exists in all of us a threshold for behavior we won't tolerate. If one nagged Gandhi long enough and he said "Get out of my face" with an angry expression, does that mean he was always an angry man? There are a few instances where even Jesus expressed anger about something (Satan's temptation; commerce in the synagogue).

I think a more accurate way to bring out someone's true nature, is to present yourself to them as one who needs them more than they need you. When someone knows you're in need and that they can make or break you without immediate consequence against them, there are those who would take full advantage of the ego boost by controlling you, bullying you, disrespecting you, and making sure you knew it was their hands you were eating out of, and how you should be grateful for it.

The constant rejection the Nice Guy receives is like that nagging. He's not inherently angry or misogynistic. It was his pre-conditioned ideal that "women like men who are nice and respectful" being chipped away over the years. So when that threshold is reached, his inappropriate reaction is saying, "I was told by society that women would be attracted to me if I was nice to them, but that doesn't work, and it's fucking with my worldview, and my only coping mechanism is to say un-nice things to women if they don't respond in the way I was told they would."