News Nintendo Says Component Shortage Could Finally Slow Down Switch Sales

...the Switch, which has been the best-selling console for over two straight years even though it’s a last-gen product...
A "last gen product" in what sense? It only came out four years ago, and is the only major dedicated portable gaming device on the market at this time. The PS5 and Series X are not really directly competing with it, as they are not portable. The switch can also be used like a console, but that's arguably not it's main selling point. It's a bit weird to compare ~200 watt consoles against a portable device that only draws 11 watts in docked mode. If anything, its main competitors in the portable space would be smartphones and tablets, where it still seems to be fairly competitive in terms of performance and features.

I also wouldn't expect a "next-gen" switch successor for maybe a couple more years. There's rumored to be an improved version coming later this year though, and that's perhaps part of where these shortages might come from, if it's utilizing newer hardware that's less readily available. The existing device is using a 2015-era Tegra SOC built on a 20nm process after all, while the new version will probably be using something built on a more modern process.