Why isnt there a faithful Linux remake of the macOS desktop environment?

Which one? The Mac changes with every iteration of the os. Some might argue not always for the better.

ElementaryOS was kinda polite in a modern mac-like way last time I looked.

Or are you referring to mac os 7 style? There was a project awhile ago to implement finder-like file windows. Forgotten its name.

Why? When you can use MacOS itself?

That's a bit like using black-face instead of hiring real black actors.

Why should there be?