I think that’s as close to a confirmation of BC as we’ll get prior to an actual hardware reveal.
Not to knock on you, just using your post as a springboard - but this has
nothing to do with BC, and I see it brought up all the time.
Bowser is an exec signalling to investors, not gamers when he says stuff like this. "A smooth transition" has diddly to do with people
who already are buying a Switch 2. He's talking about using the accounts system as a way to directly market to customers and convince them to Switch. He tells you directly:
Creating the Nintendo Account will allow us to communicate with our players if and when we make a transition to a new platform
You're going to get an email when the new Switch comes out. You're going to get alerted when you boot up your Switch. You're going to get an alert on your phone. It's going to list exclusives on the new machine that you might like based on what you've purchased in the past. The email is going to link to the phone app which opens a transition checklist.
Yes, BC might make a transition more compelling, and smoother. But that's not why they're talking about the Nintendo account. They're talking about a changing relationship with customers based on not having your accounts be tied to your machine anymore.
Nintendo will make a non-BC device in the future. Maybe it's the Switch 4, losing compat with Switch 1. Maybe it's a new pokemon handheld. Maybe it's a VR headset. And when that device comes, your Nintendo account will be there.
If Bowser were signalling BC explicitly here in public, then they'd be saying it to their partners, but they aren't. At least one Studio You Have Heard Of
still* doesn't know if their existing games will be available on the new device day one, or if it will require a port.
I think Nintendo are very foolish if they don't deliver BC, but I don't think this Nintendo Account stuff is about that. It's about Nintendo ceasing to reboot their whole account structure every time a new console comes out.
*I say still, the most recent thing I heard is ~a month old.