I'm surprised since many computers still struggle to emulate even the PS2. Is this because the PS4 and newer consoles use less exotic hardware/architecture? I understood this to be why the PS3 is almost impossible to emulate.
Quick answer is: yes, PS4 (as well as Xbox One) is x64 based, with an AMD GPU that's also available on PC (with some additional features that can probably be done still on GPU).
A proprietary emulator is both sad and extremely sketchy. Most major emulators at this point are free software and thrive because of it. I hope there is a free alternative in this space.
What a horrible, horrible experience it was to visit that page.