Unions do not exist in a vacuum. They have to operate in the same fundamental power structures as everyone else.

If union A is like "work less let AI take the slack" and union B is like "work the same, use AI to achieve more, let AI help us win" I'm joining union B every time.

Unions also require the right structural conditions.

For example waste management generally has very strong unions in the developed world because 1) capital intensity 2) operations immediately seize on labour withdrawal 3) consequences of strikes are in a golden zone of painful but not existential so are tolerated 4) extract a relatively small proportion of local gov funds, so don’t create that much powerful opposition 5) labour force is locally concentrated and highly socialised.

Those pillars of power don’t rely much on any particular legal or political system.

If you're not getting a part of that "achieve more" profit, why should you care? Because I don't see the profit being shared with the workers, at all.