This feels... Unlikely to be a thing of unions. Seems just as likely, if you saw promotions that were unwarranted, that there was incentive for management to get more promotions. Indeed, it is often to grade managers on how many promotions they have overseen. Not shocking that measuring that would cause them to happen unwarranted sometime.

Which is just too say that a healthy organization is hard. There are no panaceas.

I'm mixed on unions, all told. I don't like the dichotomy they enforce between management and workers. This often exists anyway, so I can't blame unions. And it is also true that individuals don't have the leverage for negotiation that groups do, such that it makes sense on why they can get better conditions when just between company and group.