This seemed likely the case to me as well. I'd be interesting in hearing any counterarguments (or better still, actual studies) concerning distribution efficiencies.

The price for electricity is mainly driven by cost of distribution not production. Reducing losses on distribution would further increase the cost of the expensive part (upgrade to SC net) and decrease the cost of the cheap part.

Storage would help, the cheapest production cannot run continuously.

Transmission losses are a concern because they require building huge, very high-voltage structures.

Superconductors could make transmission lines much more compact, sturdy, weatherproof, and less vulnerable to sabotage. You could run a thick armored cable instead of a set of open-air wires on tall towers.

You would no longer need high voltages at all. We only use those to cut down on those very transmission losses because we're trying to reduce the amount of current. So you can drop all of the step-up-step-down stuff. On the down side: a short is then practically unlimited in current.

Exactly the point.

We will still need some step-downs, because current density is limited. But we will need fewer of them, and they won't need the monumental cooling they have now.

Superconductors have a limit on the current they can carry before the superconducting phase breaks down. This might put similar limits on the voltages.

I agree that the nature of this is entirely different to transmission losses, but I don't expect 230V lines carrying tens of thousands of amps. This would probably require excessive amount of SC material.

Exactly, NorNed has an efficiency of 95% https://en.m.wikipedia.org/wiki/NorNed

No, exactly not. The cost of infra is dominated by the transmission network and that transmission network is very expensive to build and maintain, a superconducting network would have some massive advantages. Besides, the losses are in the 5 to 7% range for a typical grid which may sound great in theory but is still a function of the distance between the generators and the consumers. So you can't really put those where you want them, you put them where you have to in order to minimize the transmission losses or you'll have to live with larger losses. Superconductors for the grid would give far more freedom in siting and would allow all kinds of neat tricks such as transporting solar power across the planet based on the day/night and seasonal cycle and likewise for wind power depending on where it is currently blowing the most.

Generating costs are a small fraction of the final price of electricity, taxes and transportation are the big ones.

If you just look at superconductors as a replacement for any old piece of wire you're going to miss out on a whole bunch of advantages, it is a clear qualitative difference which enables solutions that are entirely undoable today. Yes, there is HVDC, but the lines are expensive and due to the high voltages involved are not easy to interface to or from. They do have some unique advantages, being DC they allow non-synchronized grids to be connected.

Transmission losses aren't a big problem for the grid precisely because we know we will have transmission losses, so we don't do things that will incur unacceptable losses.

The whole "plate a desert with solar power and solve the world energy problems" doesn't work because the desert isn't where the power draw is. Superconductors hypothetically permit the African desert to supply Europe with power.

As this goes from science to engineering, we may find other issues with that plan, beyond the obvious expenses (for example, current limits can be handled with more wires, but if the current limit is sufficiently small that's still a problem, this is no solution if the superconducting bundle has a hundred square meter crosssection), but superconductors at least put it on the table. Conventional conductors do not.