This is a pretty common and old idea, dating back to the original xbox, which was basically "just" a normal pentium processor with an nvidia gpu.
For various reasons, though, this sort of emulation has a lot of pitfalls. Either you directly run a lot of the console's firmware and e.g. try to implement the hardware devices in QEMU, or you try to recreate the console OS/firmware at a higher level, mimicking the underlying APIs. Neither are easy tasks. Take a look at the original xbox -- the emulators available aren't really great, even after nearly 2 decades of hard work.
Of course, any complex emulator is hard -- just pointing out this isn't really as much of a shortcut as it may seem. The biggest upside is just (potentially) performance, as you don't need to interpret or translate CPU instructions.
I don't think your statement about 2 decades of hard work on OG Xbox emulators is totally correct - the real focus on emulation only began in the mid 2010s. It's lack of exclusives also results in a lack of emulator developers.
That's fair -- development has been off-and-on, and there's not much of a desire for xbox emulation.
Still, I think it's a good example of how just because the xbox is basically a regular Pentium III system with a modified GeForce 3 GPU, doesn't mean it's easy to make an emulator for. And the original xbox was more "PC-like" than the PS4/5 or current xbox lineup, I'd wager.
There's more to hardware architecture than just "x86". The PS4 memory bus is completely shared between CPU and GPU, meaning that addresses on one are valid on the other. Emulating that on a general-purpose system with PCIe would be astonishingly ridiculous.
>Emulating that on a general-purpose system with PCIe would be astonishingly ridiculous.
Even official PC ports suffer from that. For example Horizon Zero Dawn looses up to 20% of performance if ran on 8x PCIe 3.0 lanes.
These consoles have A LOT of custom hardware(e.g. PS5 kraken hardware decoder, with which they can have ridiculously high SSD bandwidth, at peak levels much higher than anything on the consumer market right now). Brute-force approach won't work on modern PCs.
People said the Xbox one was just a Windows PC with a proprietary UI as well, but you really have to understand what went into making it before you determine if that’s true:
But yes, if you could break the security and implement the (many) private APIs, you wouldn’t necessarily need to emulate (although it might be legally and technologically easier to emulate a ps5 than re-implement everything).
They’re entirely different ISAs, for the most part. 3DS uses a 32-bit ARMv11 core (and an ARMv9 for compatibility) and Switch uses a 64-bit Tegra X1 based on ARMv8-A.
