There is nowhere near the hype for the Switch as there was the Wii. It also suffered major stock problems in its boom days.
The Switch is a replacement for both 3DS and Wii U. It's no surprise that it's sales are big despite a lack luster software line up.
I think it sells great the first 3 years as all the big Wii U and 3DS franchises hit the platform. Then sales will settle down.