It seems to me looking across (modern) history that the biggest threat to monopoly is government intervention. It certainly seems true in present times when you have many politicians on the left clamoring for raised taxes on the rich, as they have pretty much consistently since the beginning of the 20th century.
In The Affluent Society Galbraith points out that when he's writing (1970's) this kind of pitchfork-and-torches thinking has ebbed, but now in 2022 it seems to be back as both inequality has truly increased and the rich are making ever greater shows of their wealth. Like by going into space or owning yachts so big you have to request local bridges be dismantled to accommodate them.
To this end, wouldn't it make sense for corporations like Amazon and Starbucks, with massive profits and incredibly wealth CEO's, to at least appear to "share the wealth" and go along with, rather than prevent, the unionization of their workforces?
I get the whole "labor vs. capital" thing, but with so much excess in the system, doesn't the short-term support of higher wages and unions protect the people at the top from the very types of things that might promote government action against their considerable market advantages? It seems it would be a pittance to pay the workers at Amazon considerably higher wages and there would be considerable benefits to be reaped besides, in terms of a more quality workforce, greater customer appeal, and a lessing of calls for greater scrutiny and taxation.
I'm asking from an economic and not political point of view. If you're about to type a reply with the word "Marxism" in it you're probably not hearing my question.