I don't think your appeal to authority matters. Let's look at the data instead.
Every single monopoly to in existence today is a government granted monopoly. Let's compare the lists shall we?
Phone companies: Granted Patent monopolization by the Federal Government. Granted local government monopolies. Granted Ginormous subsidies and tax exemptions by the federal government. Granted every eminent domain and right of way by the government. Granted National monopoly status by the federal government .
Railroads: Granted Right-of-way everywhere they wanted by the Federal government. Granted massive subsidies by the federal government, some of which were on a per-mile basis and were exploited by building of railroads in meandering routes looping back and forward. Subsidies were rife with fraud. Granted tax exemptions by several states. Granted patent monopolies by the federal government. Finally taken out when the federal government decided to grant the same monopolies and assistance instead to auto companies and road makers.
Granted patent monopolies by the federal government. Granted tax exemptions at every level, federal, state and local. Granted local monopolies where throughout the majority of the USA you can have no choice in cable provider. Granted right-of-way by eminent domain in many instances.
Media conglomerates/monopolies: Granted perpetual copyright monopolies. Granted patent monopolies. Granted enourmous tax breaks. Granted monopoly over public electromagnetic spectrum.
CIA/NSA/immunized companies: Granted monopoly over drug trafficking. Granted monopoly over spying on your private data and using it for 'leverage'. Granted immunity from prosecution from violating constitution. Granted immunity from prosecution from torturing. Granted immunity from prosecution for war crimes.
Wall street / goldman sachs / investment firms: Granted immunity from prosecution for fraud. Granted immunity from financial regulations. Granted immunity from bad investments. Granted monopoly on front-running. Granted immunity from creditors.
Banks: Granted monopoly in creating money out of thin air through fractional reserve banking. Granted immunity from bad investments and creditors via FDIC.
I could go on and on. In fact every single "service" provided by the government is a de-facto monopoly at the federal or local level. If I'm unhappy with my trash collection, I'm free to pay a private company to do it, but I cannot avoid paying for the government-granted local monopoly company. I'm not allowed to choose who builds my roads, credentials my medical practitioners, provides law enforcement, provides electricity and gas etc etc. If you take the time to look into the price these monopolies are charging you, they are very inefficient. It costs for example on the order of $100k to replace the wooden poles that hold up your power lines. That's $900 for the actual wooden pole, $1000 in components and $98k in "labour" from the police department and electric company. Examples like this are everywhere you look. Think Halliburton. But I have to stop at some point. Let's see the other side. What companies has the government tried to prosecute for being a monopoly?
Microsoft: Granted patent monopolies by the federal government. Granted tax exemptions at every level. Despite this, not actually a monopoly in any other way. There are plenty of alternative operating systems, search engines, office suites, web servers etc.
Google: Granted patent monopolies by the federal government. Granted tax exemptions at every level. Despite this also not a monopoly.
ATT and Ma Bell: Yes, definitely a monopoly, but admittedly a government-created monopoly.
Railroads: Yes, another government-created monopoly.
What is the correct number of companies to have in any market? Nobody can answer this. That's why we have an economy. It may be the case that for some markets, one very efficient company is the best value proposition. However, if it decides to take advantage of it's status as a single provider, in a free market it becomes beneficial to everyone around that company, before and after in the supply chain, to force it back in line or bypass it.
In a free market, monopolistic companies cannot actually leverage their status without creating massive opposition to such moves and generating openings for competitors. That is, unless government intervenes and uses violence to enforce the monopoly status.