Cartels are also bad for markets, but aren't monopolies either. Monopolies have become a deprecated technology, but vertical integration lives on in new ways that resemble a feudal system more than a single empire. The economy as a whole has gotten so big that there is room for more than a single player at the top, and so we get cartel-like behavior between the largest players instead of full-blown monopolies. Each of them is large enough that they can ignore unrest from their customer base, and as a result they have more incentive to cooperate than to compete. The difference between Microsoft and Apple isn't the quality of their product anymore, it's a brand of tribal identity.

As abusive, anti-competitive practices continue to be improved on, we should not be constrained by outdated theories that only focus on 19th and 20th century phenomena.

The same applies to censorship. Manufacturing Consent described how the western powers could have the effect of censorship without outright censorship, and that's from over 3 decades ago.