I think it's prudent to be on an older node, using stock that's more abundant, even if it's older - especially if it still performs the duties well enough. You're 100% on the cost side of things, especially considering that Nintendo has never had any consoles that were crazy expensive. Everything was always supposed to be family friendly and therefore family attainable.

I still think battery life is a higher concern for them than sheer power when in handheld mode though, and that's a key differentiating factor between a Deck and a Switch, besides the Nintendo first-party library and chip architecture. It's really cool that the Deck is flexible enough to do both high performance and low performance tasks with toggles for the draw.