Well, it’s no longer an illegal lottery. So that’s good.
It’s just a rigged lottery. Slightly different thing. Also illegal, but for slightly different reasons. More unethical and fraudulent than before.
So it makes things better, and then makes things way worse.
Any regular hex nut works just fine as a jam nut. Basically, a jam nut is when you jam two nuts together. (It is gay, because the nuts do touch.)
And note that those nylon inserts kinda only work once. The bolt carves a thread into the insert when you insert it, so it will be weaker the second time you insert it.
Honorable mention: cage nuts. A square nut, permanently attached to a fastener that can snap into a special square hole in a 19 inch server rack. When you tighten the bolt against the nut, it tightens against the fastener, so that the nut, bolt, and fastener are secure against the square hole.