Some key insights from the article:
Basically, what they did was to look at how much batteries would be needed in a given area to provide constant power supply at least 97% of the time, and the calculate the costs of that solar+battery setup compared to coal and nuclear.
Coal has long been unprofitable, and nuclear has always needed huge state funding (you get weapons as the byproduct of nuclear power, hence the subsidies). Until it beats gas it still isn't cheap enough imo. Gas of course is still massively subsidised too though, and that's where we need to continue to work: our policy makers need to end fossil fuel subsidies