Great insights.
It is true that some American labor unions have hurt the reputation of the labor movement. The Teamsters come to mind.
No matter the form of organization, people matter. Selfish leaders can make almost any organization behave poorly, no matter the hopes of the rank and file.
Interesting, too, your point about "to whom responsibility belongs."
It's easy for a union to say they are responsible only for winning more money for their members. And easy for a corporation to insist they are responsible only for winning more money for their shareholders.
In the short run, both look right.
UNFORTUNATELY, in the long run... Unions and corporations seeking their own selfish objectives can ruin a company, bring despair to a town, crush a national industry, and make a nation poorer in the long run.
I think of my uncle, an SVP at International Harvester. You and I remember the once giant company. Life was great "until the damn unions ruined it." We know that there was a giant portion of blame pie for the corporation to eat, too.
This is not easy stuff.