They've found references to SaveMGO in the MC versions code, so there's absolutely some stuff they didn't have anymore and were only able to get due to the preservation efforts of fans.
You can keep trying to belittle the Devs efforts but it...
I feel you're missing the point of the emulation, it's an example of how deeply ingrained in to the PS3's OS the game is, not an exact comparison of the work. They had to make the emulator significantly more accurate just for MGS4 and even then...
A bunch of stuff would have had to be remade from the ground up, the game didn't even have it's own save system, it just used the PS3's own internal save system, so it couldn't save without access to the PS3's OS.
There's stuff like this all...
And with that, the last of my old reasons for sticking with console over PC is gone (Nintendo still an exception for now at least).
Guess I'll stick with the PS5 and hope PC components come down towards something reasonable in 2-4 years, if they...