Hello again, and thank you for your answer!
After doing some research on my side too, I found out that when the 2023 (UE5) update came out, configuration/save files were directly merged as the 2023 one, and not the 2013 (Unity) one anymore (Meaning : 2013's directory used to be the one 2023 now currently uses). So for Windows directory, your fix was actually more than right, thank you for fixing my mistake!
Now for macOS, it appears that it never changed its place, and after double checking on Mac, I noticed that I made a mistake with the configuration file path, being the config file. Put it by error as ".ini" which is, as you stated, being used by Ureal Engine, and not Unity. For the Unity version of macOS, the config file format is ".cfg". I corrected that mistake of mine on its PCGW page.
For Steam Cloud, I technically believe that, when the 2023 update wasn't out yet, the game didn't have any Cloud system until now. But as you also mentioned, the system is terrible because it can literally still take note of "PlayerPrefs" as a "Cloud" itself, if you get my meaning. Now that I might be doubtful as well, the best we can do is putting Steam Cloud's state to "Unknown", since we will have to dig in deeper. I will change the Steam Cloud's state too.
Reason why I quickly added back the macOS directory is because, as I said, checked directly via Mac, since I was the one who added the macOS paths that you removed, the one with the .ini mistake, of course, which is likely another reason why you removed them, since it was maybe "a copy-pasted" path from the 2023 version. So either way, you did good removing them as well!
If you want a gameplay experience of my P.O.V in the macOS version. It's itself pretty messed up in this game, due to the fact that the game uses obsolete frameworks/codes that macOS rarely support them in Unity, ending up being laggy, buggy, etc. In short : The macOS of the Unity version is extremely rushed.
I appreciate again for your answer, and I will put this topic as resolved. :D
All the best!