Thankfully its an academic debate now anyway, because solar and wind prices are already much cheaper with no end to their continued improvement in sight.
Has large scale energy storage been solved? I know there are a number of ways to do grid-scale storage, but are any of them scalable enough to power the entire country from solar and wind? Especially if another "storm of the century" (which seem to be happening more frequently now) reduces solar/wind output from a significant portion of the country so you need to draw deep into storage reserves.