So... how do we solve private monopoly?
I was never sure why the ownership class preferred one large investment over many smaller or even medium sized ones. Apparently diversification is only good for /my/ portfolio.
The reality is, the current government security state prefers this arrangement, as it vastly simplifies their strategies for mass data collection and abuse. There used to be 30 cellular companies. There were so many they felt entitled to tell the government off when they overreached. Widely seen as a problem by law enforcement the message was received and enforcement of anti trust laws in certain sectors ceased.
Is there any reason you want to isolate it to one thing? Does that benefit the discussion in any way? Were you trying to project that you don't believe anything such as a modern monopoly can be said to exist?
Monopoly comes in many forms, and only the most limited version of the argument puts it at "100% market control," whereas, if you read the many good laws that were passed in the wake of consumer and market harms, you'll see there are four specific elements, any of which, are not only a criminal act but are widely considered "monopolistic behavior."