I agree, these two things feel unnatural and do not fit in the game. Many players bind lean to the same buttons as Move Left and Move Right, which makes them automatically lean when they are moving side to side. In my opinion the best way fix the lean issue is to slow down the movement whenever the player is leaning. This would counter the keybind abuse as it would slow you down. This is the way it used to be in ArmA 2 too.