I'd argue it was after First Contact. The great thing about First Contact is that it gets both to the heart of the idea of what Star Trek is about and the limits of that idea. The film's secondary plot revolves around Zefram Cochrane, who didn't design the warp engine to usher in a new age of humanity, he did it for money (and women!). He even got sick of the hero worship and tried to run away from it all. But during the launch of the Phoenix and meeting the Vulcans, and seeing how important his discovery is for humanity, Cochrane evolves and becomes the person everyone saw him as. Humanity's evolution as a race personified.
On the other side of things you have Picard. The movie's first point of contention is that Starfleet is sure about the E's crew, but not her captain. Starfleet thinks that if Picard comes into direct confrontation with, it'll create an "unstable element." ...And it does! Picard comments to Lily how that, in the twenty-fourth century, humanity has evolved to a higher point; a point at which money is unnecessary, Earth is a paradise, etc. But as the movie progresses Picard becomes increasingly unhinged, seeking to hurt the Borg more than doing what's right for the situation. In the end, it takes the twenty-first century, lesser-evolved human to talk some sense into Picard. He is, at his worst, no better than the humans from which he's claimed to have evolved. This also asks, though weakly, if humanity can ever really evolve, and it's really only better circumstances that allow us to be more generous.
And the fourth season of Enterprise was pretty good.
