Thank you, Lachlan, for that importnat information. Did your father ever record the tune?

Another thread asserts that the name of the tune is "really"
"Dr. MacArthur's Farewell to South Uist." Apparently that's simply a misrecollection of the actual title. (I.e., another example of the "folk process.")

The only reason I can imagine for anyone not regarding the tune highly is that they associated it with a >sniff!< TV series.

As composed by Iain Mac Lachlan, there's nothing "unfolk" about it.
The name of the composer has no bearing on the style.