Those numbers make sense to me as PS4 has a tonne more games than Switch, so lower sales across a higher quantity of games is giving it the edge. Although the fact that Switch is within spitting distance of PS4 with less than 1/4 of the PS4's userbase is still pretty amazing!
Plus, I think it's safe to say that a larger proportion of Switch's software sales are 1st party compared to PS4, which means more profit per sale - which I'd imagine means a larger overall profit, which is really the only number that matters (to Sony & Nintendo anyway).
Exactly, the fact that a device with 1/4th the install base is even comparable at this point is insane.
And I think it's safe to say Nintendo is making a great amount of profit on software as their break even point for their games is relatively low. For Zelda they needed to sell 2 million units to break even, and it's well over 10 million units sold in less than 2 years. There's literally no way to spin this negatively yet people find a way.