Sounds like you have never used a good flathead screwdriver. Most of them are cheaply made and so have that problem. With a good flathead screwdriver that problem doesn’t exist (they don’t need to be in axial alignment). I’ve had the pleasure of using a good flathead screwdriver exactly once in my life - even the expensive ones are typically made wrong and have all the problems you state.
Sounds like you have never used a good flathead screwdriver. Most of them are cheaply made and so have that problem. With a good flathead screwdriver that problem doesn’t exist (they don’t need to be in axial alignment). I’ve had the pleasure of using a good flathead screwdriver exactly once in my life - even the expensive ones are typically made wrong and have all the problems you state.