I've got to say, I never saw the N64 as a 'leap' over anything.
For me personally I found the N64 to be very innovative for its time in design and pushing graphically the cartridge based console further, whilst also beating the pirates. It just seems to me that Nintendo never want to make another 'mind blowing generational leap' console like the N64 again
What did you see it as being a leap over?
It looked nice at its time, but I'd say it was firmly of the PS1/Saturn generation, where each one had their own special powers, and weakness

.
I think by the DC/GC/XBOX/PS2, everything was looking very similar.
I think if Nintendo do well with the next console, it'll be because of some innovative spin on the design of the system or the controls, that's what made the Gameboy, DS, Wii and Switch their most successful machines by some way. I guess the Wii U was different, but just not enough. I loved my Gamecube, but it was just a nicely-styled little console ultimately.
Trying to out-polygon the big two is pointless and can people even tell anymore when you throw in another million transistors to make a shadow on a tree in the background look nicer?
en.wikipedia.org
Mind you, I thought the N64 never did that well, but it seemed to outsell the Megadrive!