canon does what makes them money.I shoot weddings and it seems that nearly every wedding videographer is now using Canon. I usually see one or two videographers with several Canon DSLRs and a bag full of Canon lenses (and perhaps a few Zeiss). In the past, all of these videographers would have been using Panasonic or Sony video cameras. Lenses like the 70-200/2.8L are extremely popular among videographers. As far as I can tell, Canon has sold a heck of a lot of cameras and lenses by adding video to their EOS system.
with declining DSLR sales video seems to be a money maker.
This monitor is a high-end tool for specialists and is priced accordingly. Apparently there is a market for such thing.