Because 200 hours spread out over the course of available playing time is like 10 months for me. That's a huge investment just to reach the peak of where I feel I want to be as a character. And honestly, people can state that the game doesn't begin at hero, but to me it does. Sure, I enjoy pk'ing some in middle levels but the opportunity for real cabal wars, real exploration (especially of areas I don't know or know well), cabal leadership and influence, and balanced pk'ing does indeed begin at 51. So do I want to spend even 4 months getting to the point where I can determine if I enjoy what I'm doing...? Nope. There are a lot of other hobbies I can fill that time with, regardless of how much I enjoy CF.
The grind takes too long. It minimizes what I can do with my time while mudding, too, point being that that time should be optimized for leveling and that is increasingly more difficult to do with a declining playerbase. Lose lose from my perspective.
If I could start a character at level 35 or 40, I'd do it every time.