You're right about that, but I want to support the original commenter a bit and point out that management isn't going away, and adding unions on top of that is not an improvement if they share the same flaws.
Lawyers are famously hated around the world. But it's almost universally better to fight one if you have one on your side. Same with unions and companies. Having worked in two companies in the last few years in the same market, in the same area, one union and one not... The difference is night and day in favor of the unionized shop.
In a working market, pitching companies one against the others could have the same effect as unions, but I think there is enough implicit and explicit collusion and perverse incentives that we are far from that ideal.