This makes US unions very all or nothing, and excessive demands from unions (particularly RE: pensions) have driven many businesses out of business and bankrupted many municipalities.

My understanding is German and Scandinavian unions are much more collaborative and are unlikely to force demands that bankrupt companies.

This is why unions have such a negative connotation in the US. A lot of people see municipal governments being held hostage by unions over pensions and early retirement, and union employees being so hard to fire that you end up with "rubber rooms" and end up associating unions with expensive enshittification of services.

Unions have a negative connotation in the US because the there is a lot of money in giving them one. The US union structure arose because they predate any legal protections. You don't need the law to protect you for a strike to kill a company, it just (mostly) prevents the spiraling violence that often would ensue.