The GeForce series cards are designed, spec'd, priced for consumer usage. Nvidia has to warranty and guarantee what they sell, consumer confidence is important.
When you're doing ML or blockchain Proof-of-Work the card becomes a consumable. Is it fair for manufacturers to guarantee them like they would a consumer desktop or gaming GPU? You expect people who play with ML in their free time to subsidize your GPU cluster?
That said, hope this gets people angry enough to make TF support OpenCL. CUDA is too pervasive.