Yikes, that sounds like a mess. In WA we have one fully connected grid (SWIS) and one provider (synergy). Western Power used to be the provider, but now they only run the power stations and maintain the infra. There are multiple electrical generation companies that run power stations, but the customer doesn’t deal directly with them. They all sell power to synergy, who sells it to the customer, and synergy pays western Power to maintain the SWIS.

There are some pockets that live outside the SWIS with a different arrangement but they are a tiny minority.

Synergy is owned by the state govt, so there is a monopoly, but it’s more benevolent to the customer, and hostile to the generators. They do what they can to keep prices low. But the infra is aging, and western Power spends increasingly more each year to maintain it and replace wooden poles. Western Power is also wholly owned by the state govt.