Your explanation works very well, but completely falls apart in the last paragraph.
Solar power production clearly is (at least in part) a post-scarsity scenario, given we literally have too much power on the grid.
Furthermore, calling the power market anything like "free" is just plain wrong. A liberal approach to market regulation here would have led to disaster a long time ago, for the reasons you described at the beginning of your comment.
The market "works" because of, not inspite of regulation.
And negative prices are a good thing for consumers, not market failure.
Wake up babe, new bottom surgery just dropped