"Alot of gamers buy Nintendo consoles as secoundary devices.
They play their multiplats on PS4/XB1, and the indie types + Nintendo games on the Nintendo consoles."
I think this plays into that saying.
Very true, it's safe to say that half of these "30%" also have a good gaming PC. I would be very surprised if 20% of switch owners are "switch only" users.
Prediction: In 5 years Nintendo will Lauch a "Core Mario game" very similar to Astro Bot. That said, many will Ignore Astro Bot existence and say Nintendo created this concept.