Fair point. I can't really debate it either, as my experience of the various varieties of Irish is limited (and half-forgotten). I don't recall too much in the way of actual words and phrases varying, just accents (some, granted, quite thick). Maybe they are careful to limit their vocabulary for material for schools. Can a gaelgoir enlighten us?
Anyway, as long as anyone who insists Ulster Scots is a language gets a solid cyeack oon da nads, I'm happy to call the local versions of Irish dialects or whatever.