Does a semi-realistic design have much appeal in 2D animation?

I have some questions pertaining to animation that perhaps the more animation-savvy of you could answer for me.

HERE ARE MY QUESTIONS:

1. Why do most television animations have such a simplistic and cartoony design? Is it to cut down on production cost or is it because good animations (or the ones that have the most appeal to an audience) can't have a realistic design?
2. Why do most COMEDY cartoons have a cartoony/non-realistic design? And can a comedy-based cartoon have a realistic design and still manage to be funny?
3. Is there any realistic-artistic-style which can be used in both illustration/digital painting and animation?

I'm asking these questions because I've been learning how to draw from life for a good 5 years now. It was always my dream to get into animation, but in the first few pages of Richard William's famous book he stated that it would be wise to become a good draftsman and learn how to draw from life first before pursuing animation (so I took that to heart and I did exactly that).

I've spent 5~ years learning to draw from life (in an atelier) with the ultimate goal of getting into animation and independently making my own 2D comedy cartoon.

HOWEVER, now that I've spent 5~ years learning how to draw realistically, and I've just recently REALLY began starting to look at  most cartoons, I've noticed that they don't really require much skill in knowing how to draw from life. Most of the cartoons today (especially the most popular ones) are pretty damn simple to draw....

I'm really just wondering if my 5 years learning to draw realistically were a waste? That, and I'm also wondering if a realistic design could be used in a COMEDY-based cartoon (and for it to still be funny)?

I just don't want to have spent 5 years improving my draftsmanship just to draw simple cartoons... and to forget my knowledge of anatomy and detail and etc.

SORRY FOR THE RAMBLING. I'll try to be more concise if someone asks something directly.

Any help you guys could give me would be greatly appreciated. 

Thanks!