Warbirds had something like this. Only, not all planes used it. Only a handful used hydraulically assisted controls (P38L I believe had boosted ailerons) or flaps. Many used gears, wires, cables, rods, or servo motors to move controls, gear, and flaps.
For those that used it, it would be an interesting feature, but if shot away I don't think it would really cripple an aircraft. It would just be a nuisance if your gear dropped and slowed you down.
I was looking at some screenshots of Warbirds just yesterday, and they included pictures of planes with their gear down because hydraulics were shot away. It'd be a nice immersion factor, but so would a lot of things.
