I can attest that the same thing happened with the telephone company here in South Africa. A while after its monopoly was taken away and regulation required that public infrastructure be rented out to any ISP that wished to use it, things started thriving after a long period of stagnation.

In fact, ISPs thrived, and a lot of them are now installing and contracting the installation of their own Fibre to a lot of residences. Essentially, side-stepping the existing copper infrastructure that kept people tied to the telco monopoly.