You are forgetting one untested element and one tested.
Tested: Consumer hype and word of mouth is a powerful force that always inflates numbers. Switch's revolution may not have media support yet and may not be as easily communicated as Wii's but it is still a revolution execution in hardware design. It is a true multiplayer portable console, due to the joycon design and connectivity, and hybrid. This is what the industry wants right now with the increasing gadget and portable screen obsession. This IS a revolutionary and hype worthy quality similar to the Wii new way to play.
Untested: This quality is as much a disruption as the last point, but hard to gauge as it has never been truly tested. For the first time handheld market has been successfully combined with home consoles in a seamless design. This attracts those who just buy handhelds, those who just buy home consoles, those who have one of those situations but always wanted to try the other, and other situations that we may not have thought about. The Switch has strong potential to be the first console to hit the right balance between heavy hitter games, quirky games, esports titles, retro games, handheld games, etc. Will this not sell as much due to the price difference despite popularity like you claim? Will the hardcore market still be graphic hungry and go Scorpio instead? I have a feeling that Nintendo released this console at the exact time it was needed to combat both the above questions and more.
I expect Switch to sell anywhere from the Wii numbers to well above the DS numbers. Time will tell.
