They shouldn't notice such a fine movement.
Don't forget the drive shafts have splines and I have just been repairing the concentina rubber boot that is there to cover the spline as it is moving length ways on the shaft. The boot may have snagged something or a hit from a flying object.
Drive shaft splines are used to transfer high torque and rotational power between components (like transmission to driveshaft) while allowing for axial movement (length changes) and maintaining precise alignment. These ridges prevent slippage, share load across multiple teeth for durability, and accommodate suspension movement.
