I meant that it doesn’t actually have to emulate much. it just runs the game as if it were native, more similar to how wine works than old school emulators. with the older consoles, it has to translate the instructions from the original code into instructions for the PC hardware and insert software approximations of stuff the hardware does on the physical consoles. this invariably makes what used to take just a few instructions take multiple hundreds of clock cycles or worse.

but on the ps4, it’s just a “fancy”, underpowered desktop pc. (fancy, as in, they talked Intel/AMD into providing a custom version of their normal cpu/gpu that could run within the power/thermal budgets of the ps4 – so it runs slower than it would if you built the computer yourself.) it’s not easy to get the games themselves running as a developer for the emulator – you have to teach your computer how to read the executables and interpret them + provide system library equivalents, but you don’t have to fake entire pieces of hardware that don’t exist.

the ps5 is even further down this path… it’s just a low tier desktop PC running a custom OS built on top of one of the BSD’s (iirc). it’s why the ps5 -> PC ports come out so much faster than previous gens – don’t have to do all that much as a developer to get it working on PC. I’m honestly surprised we don’t have a functional “emulator” for it already.