Even if Switch was limited to former Wii owners, it would still have a much higher potential consumer base if most of those Wii owners wanted a Switch. The reason is Wii wasn't commonly owned by just one person, it was usually communally owned or used, by a household or a family. If you lived in a house with 4 or 5 other roommates, it's unlikely you'd have more than one Wii between everyone; but you might have 4 or 5 Switches down the road. This is why even though way more DSs sold, just about every DS owner had a Wii at home - even if they didn't themselves own a Wii.
It's also why I like the Switch hybrid so much, because this can work with Switch alone - a household with one Switch as the community console might turn into a household with 4-5 personal Switch consoles (speaking from experience).
I describe myself as a little dose of toxic masculinity.
