Tastes differ. Your results may vary. Artistic frissons not available in all areas.

As others have said, it ain't the classical training, it's what you and your accompanists do with it. Nonclassical singers can be awful too. I'm thinking of the kind with expert musical skills (in theory) but who think trad has to sound like pop to mean anything. Meanwhile, they and/or their musicians, are doing the jazz riffs and the bongos, etc.
Not that fusion is necessarily the kiss if death, but it *is* almost impossible to carry off. (But that's just an expression of my own taste.)

It also depends on your expectations. If you like bel canto and sit down to listen to a classical setting of a folksong, you won't be disappointed. If you sit down with, say, Harry Cox or Alameda Riddle as your standard, you will be.

For a somewhat less dramatic contrast, compare Jean Redpath's renditions of Burns's songs in the artsy arrangements of Serge Hovey with her less elaborate performances elsewhere.

You can't much help what you like or don't like.