and protections (i.e. regulations) were put into place to prevent exactly what happened in Texas, throughout the U.S.

These companies are pure monopolies in most places and you can now include Cable/Internet service providers.
And since 1980's, these public companies have been Profitized (instead of Privatized because words matter) to the point where we can't go anywhere else for these services.

These companies own the last mile to our houses.
That means no competing company can charge a lower price because the owner of the last mile can fee them to the point where the competing company can never offer the best price.

If you don't know what the last mile is, here is a wiki page.