Genes vision: The future will be full of gorgeous women in miniskirts. Don't really have a problem with that one. 
Seriously though, the level of humanities "perfection" changed considerably between TOS and TNG. In TOS, despite solving many of them, people still had issues and problems, but they mostly tried to deal with it rationally. Hate and prejudice still existed (like in Balance of Terror), but people were rational enough realize they had a problem and fix it.
In TNG people were just "perfect" and largely unquestioning about their perfection. It makes ships like the Galaxy-class perfectly understandable when you realize it was made by a society that had it's head stuck up it's arse.

Seriously though, the level of humanities "perfection" changed considerably between TOS and TNG. In TOS, despite solving many of them, people still had issues and problems, but they mostly tried to deal with it rationally. Hate and prejudice still existed (like in Balance of Terror), but people were rational enough realize they had a problem and fix it.
In TNG people were just "perfect" and largely unquestioning about their perfection. It makes ships like the Galaxy-class perfectly understandable when you realize it was made by a society that had it's head stuck up it's arse.