Monopolies are an interesting thing.

Ruthless competition can make a monopoly, but usually it is short lived.

To really have a monopoly, you really need a govern-cement to implement barriers to entry. Such as, right now it is almost impossible to start a new car company. Which proves that Tesla was in bed with those who control the govern-cement. How Musk cut through so much red tape, so quickly is amazing.

But, what always destroys monopolies is innovation.
A monopoly gets big and slow, and thus easy to outmaneuvre.

It many developing countries, hard phone lines are not even being installed. It is far cheaper to just put in cell towers.

AT&Ts days are numbered. They have fallen short on their promises too often, and their business will soon be gone. And it will be an innovation that just makes all of their services obsolete.

Same with Microsloth. They got so big because they had access to money that the competition did not. Whether it was started that way, or the spy agencies co-opted them is hard to tell. But, Microsloth should really come with a sticker (Virus Inside).

Now, if Microsloth makes any big errors, people will start fleeing in droves to linux. In 10 years, i doubt Microsloth will exist.