I personaly liked the old way the capitalizer worked, that is capitalize all words. The new version excludes “the, and” etc.
So in the preferences I tried to delete all entries under “Usually keep lowercase in Titlecase”.
However it appears to be impossible to delete all but the last entry.
The last item is listed but the delete button is grayed out.
Preferences capitalizer fault
Youre right, that is a bug - the way to get round it would be to add a dummy entry that wont come up.
Please be ware though that if the old capitalization is different to the capitalization used by Musicbrainz, the Musicbrainz capitalisation more accurately reflects the norms.