This is kind of what I meant by pendulum swing.

In recent generations, unions have been mostly receding. Being on board regardless of form is a feature of this. Union politics was largely concerned with holding some ground. Getting specific about form is something you do on the way up, moreso than down.

Union politics in the west in the post WWII period started looking more like guilds and less like the pre-WWII left wing unions that dominated the 20s and 30s. Those unions were far more concerned with broader social transformation than those that came after, who were primarily interested in protecting only their workers and locking down seniority-based privileges. Corruption and conservativism ran through the labour movement in the latter half of the 20th century, and led in many cases to anti-union sentiment from the people they were supposed to be organizing. It will take significant rebuilding and rethinking of what a union is before they can have broad resurgence. Organizing in individual workplaces and industries means little when the vast majority of workers are working odd hours in multiple service industry jobs among several employers.