N64 and Gamecube is proof positive of why Nintendo, as opposed to their competitors, were able to maintain a $200-$250 price point well into the 2000s when others could not: better engineering.
N64, PS1 and Saturn, at their time, were the top tier for 3D modelled games and no other platform could come close to touching them; PC was actually forced to play catch-up to an extent with what these 3 were offering (mostly MIPS CPUs and proprietary GPUs manufactured by NEC, if I remember right), and began offering Voodoo1 video cards for PCs around the same time for the cost of an entire PS1 console. PS1 and Saturn were designed in a way that they were mild loss-leaders. Meanwhile, N64 had to sacrifice its margin made to achieve the lowest price point of $200, but it was making money out of the gate and STILL pioneering what 3D games were capable of.
During the PS2 and Gamecube eras, PCs were finally starting to eclipse consoles in terms of 3D gaming, but not without a cost. PC gaming hardware was becoming prohibitively expensive if you wanted performance that eclipsed a console. Sony maintained its $300 launch price by over-designing the PS2, Xbox came in at $300 due to under-designing and taking a huge hit on hardware to enter the market with essentially a PC in a console box. And meanwhile, Nintendo kept pace with both of them and the current PC hardware market at the time for $200 and little to no loss on hardware sold.
And we all remember what happened with PS3 and 360. Both over-designed and bleeding-edge for their time at launch, well above what PCs were capable of in that specific moment, they shattered expectations of what hardware was capable of, and prices ballooned to match. And then there was the Wii, which I won't even bring into the discussion.
So while this generation was a "return to sanity", as you described, Nintendo has had a long history of designing hardware that can match the industry standard both without loss-leading and still being cheapest to market. Their engineers have been capable of outright miracles before, and I don't see how matching 3-year-old consoles at a cheaper price is a miraculous feat. I am just not seeing how Nintendo achieving what it's been consistently been able to achieve up until the Wii is somehow unfathomable.
There is no magic 28nm cpu and GPU tech that only Nintendo has access to that sony and Microsoft don't, especially with the same or similar vendors at play. Whatever incremental improvements made to the chips that are on that node since late 2013 could certainly make it into their new machines, but it's not going to be somehow cheaper AND more powerful than their competitors. Pick 1.