The important quote from the article
What the launch sales of Switch 2 primarily tell us is that they made a lot of Switch 2 to sell at launch. Lifetime sales and launch sales of a console often do not correlate, meaning that some consoles with small launches ended up doing incredibly well lifetime (PS2 only sold 400k in its launch month) while others with big launches ended up not doing as well lifetime. Since launch month demand is rarely satiated by available supply (and it is certainly not a great sign when it is, historically) all we can really get a read on at launch is the confidence of the manufacturer to make so many units available, and the ability of the supply chain to get those units into the market.
This is still very positive news for the long term viability of the Switch 2 because having a solid install base means third parties have more incentive to port games to the system.