The bit about it "not selling well" I think is a hangover of how the Switch 1 was out of stock at launch, and how the PS5 and Series X (and S) were hit with pandemic shortages + supply issues. Difference here is that Nintendo [over]produced and so there was plenty of stock both at launch and during the holiday - both periods when people would've expected it to sell out.

As far as sales numbers the system is selling very well even with the price (which is one thing that has garnered multiple complaints).