Something I've always rather felt is, that Star Trek is kind of...too perfect, at least the TNG era feels that way to me. It seems to me that in some ways, Star Trek in general, is rather unobtainable, in various ways.
Technology: As it stands now, most technology in Star Trek is still very very within the realm of sci-fi, and until such a time as proved otherwise, isn't currently obtainable for us within the early 21st century.
United Earth: This is the big point to me. Not so much the united governments, but more humanity as a species, at this point in time, I do honestly wonder if humanity could truly put aside all differences and such, and unite for all time like that.
Aliens: Most sci-fi series make aliens be our allies or our enemies, or a mixture there-of. While I don't want to get into an argument on if aliens exist or not, just that if they did, I honestly wonder how...benevolent they might actually be. I mean, what would humanity truly have to offer the greater galaxy?
There's more, but I'll leave it with that for the time being. Do you all think that 'Star Trek' is possible for us in reality?