And they were too timid to move far enough away from that with Enterprise....They squandered the opportunity to show us a humanity that was still learning to become that perfect futuristic society.
Really, the "Earth is a money-free Paradise and humans have perfected themselves" business was one of the absolute worst ideas TNG Trek had; it took the "Earth should be a sympathetic society" dictum from the old show to an absurd extreme. It retrospect I think of it as a sign of sentimentalism starting to coat the arteries of the franchise. Even as a kid I can remember cringing every time Picard opened his mouth to talk about how humanity had "evolved beyond" the need for this or that.
They sort-of-tried to move away from it in later shows and in the movies, but couldn't bring themselves to really break with it.