the NLRB itself is a bourgeois institution that severely handicaps what unions can be. having the state be the arbiter of organized labor power fundamentally changes what unions even are.
If people don’t know any examples of this: I can’t speak for many unions, but I know that it is not uncommon (might be universal) that if workers get tired of their union (let’s say they have a good reason, like their national is being too lib or whatever), they aren’t allowed to simply reafilliate; they need to dissolve their union and re-unionize one year later