I should clarify what I meant, since it was completely unclear in retrospect.
DS launched, but Nintendo advertised that it was a "third pillar" to the GameBoy line, but as soon as the DS proved its mettle, the GBA got dropped. On the flip side, 3DS succeeded the DS 18 months before the Wii U launched, giving it time to establish itself before Nintendo left the Wii's third party revenue behind.
Sony and Microsoft have other sources of revenue, two years of losses from the Xbox and Playstation divisions during a console launch window won't kill them (though it would hurt). Two years of losses would gut Nintendo when their only corporate revenue is games related. The 3DS kept the company alive during the Wii U years, and while Nintendo is in an excellent position, I don't think they're so foolish to put all their eggs in the NG basket.
So by "looking to the DS" I mean looking to how the DS was used - how many units of software total they were delivering across two platforms, how they used the DS as an "experimental" step of the GBA, until it was clear it was going to take, how they used the DS as a hedge in the Wii days.
Right now we're are literally seeing games from the handheld world come over (Another Code, Mario vs Donkey Kong, Luigi's Mansion 2), sequels to handheld games (Detective Pikachu 2), and games which have strong connections to the handheld space (2D Mario, Mario RPGs, Princess Peach). And Pokemon will have to be cross-gen for a couple years. Sword/Shield sold more software units in its first quarter than the Switch sold hardware units in its first year. Pokemon games don't have a long tail - they need that big install base.
This is why there will be a cross-gen period - Nintendo needs to replace the handheld sales that kept the company afloat when transitioning consoles in the past. And to bring it back to hardware, this is why Nintendo needs backwards compatibility. Not because of Breath of the Wild but because of Professor Layton - all these late stage 3rd party games that are cheap to make need to stay cheap (one development target) while fattening up the Switch NG's library, leaving no reason for folks to hang on to the old platform.
I remember those early Directs with 3DS games mixed in with Switch games. If Nintendo is going to support Switch into 2025, which they say they're doing, how great is it going to be for NG owners to watch and know that they can play every single game they see, on their one and only hybrid console? How tantalizing will it be for Switch owners to see gorgeous NG games and know that if they upgrade, they're not leaving any of their casual puzzlers or play-on-the-train platformers behind to do it?
(Wii U is back).
