We sort of do this in the UK.
British Telecom own Open Reach who provide infrastructure for the country.
There is cable, for a second option in cities, and there are some regional fibre networks that provide a second infrastructure option, but for the most part Open Reach is the only option.
I had massive issues with my line, I had engineers come out and we were able to test the cables and show that there was a fault between my house and the exchange. I don't have a relationship with Open Reach so I had to rely on my ISP opening tickets and it disappearing into a black hole.
After 6 months of basically not being able to use it I had to switch to BT and magically I was able to get an engineer come out and it's all good.
Fuck BT, and the conflict of interest system where the infrastructure is managed by someone who also provides the service.
Luckily an Alt Network is laying fibre outside and should hopefully be able to supply service in the next 6 months and I'll be dropping BT infrastructure as soon as possible.
I don't care whether the system is multiple infrastructure options, or one infrastructure and multiple services over the top but in that case my infrastructure provider should be separate from my service provider.