They did increase the length of the nose landing gear, which helped a bit. But increasing the length of the main landing gear would have required moving the gear further outboard, as there was no space to extend the gear in an inboard direction when it's stowed. You can't move the gear a lot further out, or it ends up behind the engines. See this picture someone else on this thread posted: https://i.stack.imgur.com/GFzcj.jpg And you really don't want to move the engines further out, because that's going to affect the engine-out behaviour, and require a larger vertical stabilizer to handle asymmetric thrust.