No, it doesn't.That means there are really only Bad Kirks.
It just means that people get to the point were the best of intentions are still influenced by our dark side.
And how long did that take? Leyton got to martial law over all of Earth before he was stopped. He couldn't have progressed that far unless there were others that thought the security was far more important than the cooperation.The good side of the Federation recognised this and stopped them.
Pressman violated interstellar law and treaty and wasn't even remorseful. He expected to be supported by members of Starfleet Command.
Pure good is a journey, not a destination. It requires the balancing of our own needs, while not being excessive, either to virtue or vice. That is not an easy process.