Naval catapults don't apply force to the main gear either. Mostly is to the nose gear now, but it used to through the use of bridles to points on the wing (and wing spar). The bridles were a pain though, so they transitioned everything to the nose gear attachment. You can tell when a carrier transitioned, because they took the bridle catchers off the bow (the little narrow ramps at the front).

I wonder what sort of force you could generate with a series of electric coils in the ground? It lacks moving parts, so it should be low maintenance. You'd need magnets on the gear of the plane, offsetting the weight savings though. Yeah, you'd definitely need to reinforce the landing gear, but I think that's doable.