Rewind. Why did the government grant monopolies to these companies in the first place?

To entice them to invest in their area because nobody else would.

Infrastructure isn't software development. It requires billions of dollars of capital investment. That investment isn't going to go to many areas unless it's nearly guaranteed a return, hence the labyrinth of monopolistic guarantees bestowed upon ISPs.

It's not clear to me that consumer options would flourish if you were to roll back all ISP related regulations and void existing contracts. I suspect the current system would just become more entrenched.