The PS2 emulator is some of the last remaining JIT privileged code on the PS5.
Sony aggressively removed JIT privileged attack surface from the PS5, disabling JIT in both the web browser and
the BluRay player. Since the PS2 emulator is really a PS4 title that runs due to backwards compatibility, they were unable to make changes to the software, and so its JIT privilege had to be spared.
Having JIT privilege means that
fully compromising the emulator, including the compiler co-process, would grant the ability to run fully arbitrary native code (not just ROP) on the PS4/PS5 without the need for a kernel exploit.