I think this is a slight perversion of the truth. A union that relies entirely on industrial action (a.k.a. strikes) to get a company to change, isn't a good union. If a union walks into every negotiation with just an ultimatum, then very quickly the otherside is going to get fed up of their bullshit.
Ideally a union should be working closely with senior leaders to find win-win situations for both employer and employee. An an obvious example would be preventing Andy Rubin from getting a $90mil payday for sexually harassing people. Clearly that's not only a serious injustice, but was ultimately always going to end up public and damaging Google brand.
A union could help senior leaders find a better solution, part of that would be providing representation to those sexually harassed so they could bring a stronger case, and make it much easier for other senior leaders to throw Andy Rubin to the wolves.