It is possible but I just don't like that idea. I want to hide my hand and show it when I want to as a part of strategy, with provably fair everyone could easily check if someone bluffed or not and use that info.
Besides, provably fair system in texas holdem is meaningless, you will never know is it "real provably fair system" or is it "rigged provably fair system", for example you get KK, your opponent gets AA and flop shows KKA - one person will go all in other will call, one will lose and house will earn big rake. You will never prove was it rigged or not, even thought it was provably fair.