"Now you respect me, because I'm a threat"
I never thought I'd truly understand why Syndrome would say such a thing until I experienced something like that myself.
Imagine you've been told most of your childhood to shut up, go away, let the adults talk, disrespected, and that shit continues all the way into adulthood, even after you get a respectable job and move out. Then when you finally put your foot down, don't back away, and show teeth, these same adults suddenly notice you exist, and are shocked and shaken at how "horrible," "dictator-like," or "strict" you've become.
Word to the wise: don't treat kids like dirt under your feet, because they eventually grow up and become strong enough to bite back and make you pay for treating them terribly.
I know it's not exactly the same as what happened between Mr. Incredible and Buddy/Syndrome, but I can now get why Syndrome would have a POV like that, just not from a supervillain perspective.