People keep reposting this like it's a gotcha.
It's not
If prices are negative most of the day there is less incentive to provide the capacity that's needed during the night. The money for capex has to come from somewhere so it goes up significantly at night. And of course the negative price isn't "real", it just means power plants will shut down for swaths of the year until it's affordable to keep the remainder running. Which then means lower average capacity on days that are cloudy, or additional maintenance on systems that only run in the winter. So then people throw battery stuff around... batteries are expensive. Really, really, really, really expensive. So you have to find a way to keep capacity up that's not absurdly expensive or hard to maintain, or you have to keep all your fossil fuel plants at the ready while producing $0 in income to offset the upkeep, which...yes, gets passed to the consumer.
I know people want to simplify the national grid which spans across all continental states and connects to literal billions of devices producing and consuming power...but it's actually kinda complicated.