"They were smarter than most people give them credit for, they held back the launch to gain mindshare through social media and internet news cycles."
That idea doesn't make sense.
You are implicitly saying that the delays automatically equal more buyers. And the answer to that is simply no.
Wii U was first revealed in 2011 and released a year later and even though it had a 3 million shipment, Switch, which was revealed in October and released in March (less than 6 months between both periods) outperformed it, even though it had a 2 million shipment.
You speak of demand, but you don't give it enough credit.
Demand for Wii U and for Switch made all the difference.
Nintendo could have delayed Wii U to March aswell and things wouldn't have looked better. Because let's not forget, Wii U was released during Christmas and Switch wasn't!
It's not the delay that helped Switch break records - imagine if they had delayed it 3 more months! -, it was the concept and the games (Zelda, to be specific) that make it so attractive.
And you can believe that had they shipped 3 million, like they did with Wii U, and things would have been even better for Switch!