Or maybe not. It's not the weight of the fuel cell/motor combo that is the limiting factor, but the weight of the H2 storage tanks. An H2 jet engine will probably [0] be less efficient than a fuel cell + motor, so more H2 storage is required in order to reach a comparable performance.

[0] Considering the Carnot efficiency of a jet engine at ~30%, a combination of fuel cell (~60%), motor (~95%) and propeller (~80%) will still beat it by a factor of 1.5.