Well the sales are good (overall) but also show the problem.
Nintendos 1st party sales make up around 50% of all sales, which means that only around 625m-ish games come from 3rd parties.
However, sony only has aprox. 60m 1st party software sales (going by chatGPT, if anyone has a more accurate number, please tell).
Given that the PS2 sold around 1.383billion software, that's a 3rd party share of ~ 95% = 3rd parties sold almost twice as good on ps2 compared to Switch.
If we factor in that Switch has much more software to offer, we can fairly safely say that those 625m are spread across more devs resulting in even
less sales on a per game basis.