To me this looks like a purely academical discussion.
Honest: how often do you scan through your library and the filesystem in parallel?
As empty folders are not marked as empty by the file system so that you do not get any hint while browsing through the folder list, you have to open each one individually only to find it is empty or not.
And even if it is empty then this would not mean that the artist has disappeared but it could just as well be that before, there was a typo in the name and the emptiness of the folder is more than justigied.
And then you really want to enter a filter to look for the name of the artist in the program that shows the tags?
What a cumbersome process! That might work for a few dozens but that's it.
If you have that artist name in the tags, you will find it with the program that reads the tags.
MP3tag, BTW, would not even display that folder. So at least from within MP3tag this would not be of any help.
Here is a link to a really tiny program to delete empty folders: