Agreed, these predictions people are making seem absolutely crazy. Below 5 million would be disastrous in my opinion.
Let's not forget that it has its launch period, time to sort stock out and then holiday period in those 9 months, which the other consoles listed there didn't have. Its most comparable to 3DS, as you point out and I'm predicting it to do 2m less than that.
I have no clue what to expect for switch sales.
-Every Nintendo home console has sold less than the previous one, with one exception. But: Nintendo would have more of a leg to stand on and call it a portable when it feels convenient for them. So maybe could find somewhere between Wii U and 3DS sales as most realistic. -Switch doesn't have very many games in the works.But: the few that it does have are very solid.And: the switch also has a few fantastic studios developing for it that never have developed for Nintendo before. So that seems promising.
Nintendo also seems to be advertising the system far better than they did with the Wii U.
With the Wii U, I don't think a lot of people really realized it was it's own thing. Or why it was something worth getting.
With the Switch, they do seem to be advertising it, and showing some pretty cool applications of it.
What I do know for sure, is that preorders are sold out at my walmart, Amazon, and Zelda is selling ludicrously well.
I think it's probable for it to sell 500k the first day. Possibly, but unlikely more.
But after that, there's a lot up in the air. Nintendo needs to advertise hard. And they need to work on developing solid titles quickly.
It could do amazing, or it could do horrible.
I'm leaning towards the latter but slightly. Largely because Nintendo needs more work to develop titles. They don't really make very many new IPs, they only release a few major titles.
Probably being overly negative with the prediction itself, but it's a big unknown. They could do great, and exceed every prediction just like they did with the Wii. Or they could do awful and fail to reach Wii U levels.