How come the PS360wii dont come with a cart slots?

[arsenicazure]

So its all nice and cold and i decided to clean out my closet and out pops out my trusty old sega saturn. SO, i plugged it in and it works. its over 12 yrs old and still works like a charm..now im sure a lot of people havent even played a saturn, expt a lot of ppl in JPN i guess, but I was wondering why MS and SONY/nintendo ditched the cart slot, as did sega for the DC.

I remember playing Marvelvs cap with the 4MB cart and it was brilliant. SO why havent console manufacturers come up with something similar. I know its extremely ignorant of me to say if they added on say an extra 256MB/512 RAM cart graphics would get phenomenal, but there is defntly potential for games to get better, better textures, lesser load times etc? So how come no one picked up on that idea, especially SONY, considering they want their console to last 10 yrs.. wouldnt this be a good way to ensure it doesnt look as dated 3-4 yrs from now when the X720/wii HD hits?

On a side note, VF2, guardian heroes, sega rally,nights,panzer dragoon zwei you still rock

 As for Bugtoo!, ultimate mk3 and need for speed... god what the hell was i thinking back then

 

cheers