But each of the multiple names points to the same actual data, so it doesn't matter which one is shown. The obvious choice would be to show the absolute path that the OS used to load the executable.
The same is true for hard linked files on Windows. That never stops Windows from showing you a path.
There is almost always an "obviously right" path (the one used when opening the file). And if you lost track of that, deterministically choosing one of the possible paths is almost always more user friendly than just chowing inode numbers.
The path used while opening a file is easy to get confused. If your cwd changed names or was deleted since you entered it, and you open an executable with a relative path, what is the "obviously right" path then?
Really, this discussion just shows the question is the problem; if you're asking "what path was used the launch the process", that's easy to keep track of & always be right. If you're asking "what is the path right now to the file that launched the process", maybe that has no answer.
(And a program could do that itself, if it wants to.)
This was kind of in the middle of your complaint about windows, but then you've got unixy busybox discussion.
On a unix filesystem, a file that's hard linked with multiple names has no single 'actual name'. All of the names are equally valid. You could show the filesystem and inode number, which should uniquely identify the file, but is pretty user unfriendly.