6 times better resolution. That's a darn good enough reason for doing it.
can they make it widescreen? If not, why bother...
That has nothing to do with widescreen.
The whole point for widescreen DVDs is to preserve the original aspect ratio for theatrically presented movies. With TNG though, the original aspect ratio is 4:3. To convert it into widescreen would be to chop up the screen ala pan n' scan.