I guess, but the real issue here is that capital will mount a concerted, decades long effort, to prevent global organization of labor. Its not like its per se impossible to get enough global labor organization: its just profoundly, aggressively, even murderously, opposed by people who have power.
I guess we could think of that as just "part of the reality," but I think its a little silly not to at least mention it.
It is not realistic but even worse it isnt even desirable.
There is huge swaths of opposition to "global organization of labor". The last thing you want is to oppress a bunch of people under your vision of perfect government.
