I meant to say ps4, not ps5 lol.
If they could build and ship the units needed within the 12 months of 2021 (Jan 1st - Dec 31st), I predict they could sell said units IF a significant (10+ million) were the Switch Pros AND if they also came out with 2-3 mega heavy hitters Summer - December 31st 2021. By Mega heavy hitter I don't mean Bayo 3 or Xenoblade X port. I'm talking Botw 2, the next 3D Mario game, Metroid Prime 4, some new AAA IP, etc.
And before anyone starts to tell me how Metroid Prime 4 is small potatoes because 1-3 were, I believe that the game has been so hyped and talked about for so long that the demand for it is ripening like a fine wine. I predict there will be people that buy MP4 that would never have bought the game had it been an-every-2-to-3-years-we-release-a-new-game kind of series. I predict there will probably be a significant amount of hype-train-buyers that get it and hardly ever play it even. It's become the Shadow of Colossus of Nintendo games, or the next Project Rainfall situation. In fact, this goes into a larger theory I have:
I think Nintendo stops making games for series that sell decent to them (great to most studios), in order to build hype for those series so that when they DO come out with a new game they will sell absolutely massively. Metroid Prime will be the next example of that, I think. Kid Icarus could be another candidate down the road, so could Mother, maybe even Golden Sun. I think they've learned how to create enough demand for games so that when they do make them, they sell really well (therefore making the time/resources they invested into development to be efficiently spent).
Even with what you said 35mil+ just feels like a pipe dream and I'm one of those people that think the Switch has a good chance to sell 140mil+ lifetime. With a big Pokémon and most likely a Switch pro coming.