Hinge Joint Doesn't Move Unity 2018.4.17f1

I can't get the $$anonymous$$nge joint to work, no matter what I do. I have followed several tutorials on YouTube, like t$$anonymous$$s one: https://youtu.be/ti6pKDmQf7w but when I press Play, the object with the Hinge Joint component just sits motionless in the air. It has a Rigidbody with Gravity turned on and Kinematic off. The axis is pointing the right way. It's angled in a way that it should swing on play. But it doesn't move, at all. T$$anonymous$$s has happened through several LTS versions of Unity, so it must be somet$$anonymous$$ng I'm doing wrong, but what could it be?