Well, people in any old club can "just stop working". But they are facing contractual penalties including getting fired. And I think that's fair.
> In any case, the US should destroy the unions by removing all legislation preventing work organization or giving them special rights, and let them reform as grassroot unions (your "old club that people can form") and let them grow from this point.
Yes. Though removing the special legal rights (and the few obligations) from unions would basically destroy them.
No, why?
The British monarchy also didn't spring out of nowhere, but that doesn't mean Britain couldn't turn into a republic, if they wanted to change their laws.
Here in Singapore we barely have any unions, or rather in practice unions barely have any influence.
Compare also https://pseudoerasmus.com/2017/10/02/ijd/
In any case, the US should destroy the unions by removing all legislation preventing work organization or giving them special rights, and let them reform as grassroot unions (your "old club that people can form") and let them grow from this point.