[mozumder]

Smaller sensors mean bigger depth-of-field.

Shallow depth-of-field is incredibly distracting for video and difficult to work with. Everything is out of focus. It's mostly a photography/art thing to isolate your subject.

You can see how sports program would want everything to be in focus, instead of just one player. That would look ridiculous.

[alfanick]

this + Smaller sensor means larger effective focal length, which tends to smaller/cheaper lenses.

86x zoom for 35mm sensor would be much larger (so big that it would be impractical), heavier and much pricier than $200k.