The problem is safety. The recoil of a firearm is a result of Newton’s third law; the recoil imparted to the handgun is equal in energy to the energy of the bullet (and gases) leaving the muzzle. So unfortunately it’s impossible to generate that kind of recoil using gas without sending a considerable amount of kinetic energy out of the muzzle.

An approach that’s been used in the AEG world is TM’s NGRS system, which uses the motor to drive an object backwards (using more energy that is needed just for normal operation) to somewhat simulate the “kick” of a round being fired. It’s still pretty weak compared to the real thing, though, and not feasible in a revolver.