Well, no, it isn't; not unless there is some kind of evidence for that assumption; which, so far, we don't have. People will believe what they want to, though, particularly when, as in this case, an apparently false etymology has been repeated so often since its original publication about a century ago that it has become "received wisdom". (See, principally, Wm. Grattan Flood, A History of Irish Music, 1905). Fantasy is so often more agreeable than fact, particularly where folk music (in almost any country) is concerned; and especially where there are also political considerations involved.