They sure did cripple HD78xx. Also the usage of heavy compute cards for regular consumers is a joke. I would rather have 5-10% faster gaming experience than 50-100% faster compute.
If you want to compute, buy a card made for it. Then you also avoid the silly things with your "pro" gaming card that throttle or overheat under compute.
The current new Nvidia gaming card could easly be used for compute from a technical point of view. The thing that pisses me of is that they deliberalty crippled it forcing people to buy the more expensive "pro" cards. Apart from the forced crippling I doubt there would be any other major difference between the gaming card and the pro compute one.