The transmission should of course be state owned due to being a natural monopoly.
So-called "natural" monopolies are quite difficult to regulate correctly. And the solution we chose as a society a century ago might not be the right one for today.
You say that like it's a bad thing. Maybe electricity generation shouldn't be a profit seeking enterprise?
Typically, if a person/corporation is clever and figures out a way to reduce costs, they are incentivized heavily to do so because they take the gains, at least for a while until others figure it out too and compete.
With utilities, they are actively incentivized to increase prices as much as possible. This is a crucial distinction for people asking why cheaper electricity generation methods are not resulting in cheaper utility bills: because the regulatory structure is not operating the way it should, and they need to get involved democratically to change the system!
I wouldn't expect most things from 1920 to still apply today. I can't smoke inside and I don't have to drink ethanol.
This usually doesn't work out.
Really? We can't even regulate smoking? That's too far for you? Jesus Christ.
If this isn't "we tried nothing and we're all out of ideas" then I don't know what is.
Yes, regulations are not perfect and do have to be updated. That doesn't mean theyre worthless and we shouldn't bother. Thats stupid.
But, I don't think this particular thing proves that point. What we have here is a chaotic shift to a new equilibrium. Technology has changed and needs/priorities have changed.
People wouldn't overbuild solar if they could forecast that it wouldn't be profitable. The issue is they can't forecast.
The reason we aren't allocating resources optimally is not about who is in control or what their motives are. It's that we don't have the information we would need in order to be able to.
TLDR: growing pains, not misaligned incentives.