Comments from others make me think the motion controls are generally fine on the Wii U, but not the Switch. As noted I actually like motion controls. The entire issue with them here is that the motion of 3D geometry is not 1:1 to the positioning of the peripheral, so something as simple as rotating the right joycon a very specific distance and direction does not consistently match with up with the object orientation on screen. It makes the act of interacting with the 3D space using motion controls incredibly frustrating and unsatisfying, as the feedback is not in synchronicity with the input.
This is either due to poor motion control programming for the Switch build relative to the actual peripheral hardware (potentially rushed code straight from the Wii U), or the Switch motion control is actually worse and less accurate than the Wii U / Wiimote M+.