That would toss away any shot of backwards compatibility without a second processor or translation layer.

I can’t see how that would be beneficial.

A second processor isn't that crazy of an idea for Nintendo given the 3DS had an ARM11, ARM9, and an ARM7!

Famously, the 3DS has complete GBA hardware inside of it that never got used outside of the Ambassador Program.

True. But the newer consoles in those cases were huge leaps over the older one.

ARM has 100% backwards compatible CPUs that Nintendo could use. They’ve done backwards compatibility a number of times now without needing to embed an entire extra CPU such as the Wii and the Wii U. I would be surprised if they weren’t thinking about it when they were designing the Switch.

The “embed the old console“ thing always works, but why go that far if there’s a much simpler option?

Well, not paying the ARM royalites is enough to motivate them to perform the jump. But Nintendo is japanese and softbank, ARM "owner", is japanese too, namely high level country interests would short circuit everything.

Isn't risc-v similar to arm both being reduced set of instructions but one being opensource?

It is risc-v, there is a "compressed" byte code (but I would avoid it). It is more than open source: it is worldwide royalty free of an average modern ISA, and that...

It's a well known "secret" at this point what the next chip will be and it's a new Tegra. Nintendo is all in on DLSS 3.5