I like the Roberta Flack version, which is direct and simple. But apparently Ewan MacColl, who wrote the song, thought it was too pop.
It is pop, it has strings, which is why it was a big and deserved hit.
There is a new album of Ewan MacColl covers out. A tribute album, as it were. He was a giant of the Englishy folk scene of the 50s, and married Pete Seeger’s sister to boot. He claimed their version of this song was the best, stripped down and weird, but he’s wrong (though to be fair he died before Johnny Cash recorded his version).
For the record, here’s the lovely Roberta Flack version, which is also better than MacColl’s.