They aren't stupid - it's entirely possible that Apple have run the numbers and found it uneconomical to keep pro gear up to date. So they simply give up the share of the market that contains video pros and similar. Obviously they'll lose the whole families of those professionals, and perhaps their whole businesses too - but Apple must have calculated that risk.

So most likely it's simply better business to cater to the consumer/prosumer part of the market and ignore "true pro" gear.