In The Netherlands, the power grid has been turned into a different company than the power supply company. Same for gas and internet. The infrastructure companies are tightly regulated, to the point that they might as well be gpvernment branches. The providers however, are free to offer whatever.
The result is healthy competition where possible, without any company gaining a monopoly position over the utilities of individuals.
The drawback is that they figired out that the best way to make money, is of the backs of lazy people. People who don’t want to switch providers, cause that means effort. Hence, not actively looking for a better offer every few years is quite costly.