Translation:They do not speak Irish in Scotland.
Note that this refers to a specific 'they'. If you wanted a general 'they' (like often used in English), the saorbhriathar would be used:
Ní labhraítear Gaeilge in Albain
I wrote They do not speak Gaelic in Scotland, and it was not accepted. As Gaeilge can refer to any Goidelic language or dialect, I believe it would be better translation than Irish here.
Wouldn’t one be more specific when referring specifically to Irish in a sentence about Scotland, and write Gaeilge na hÉireann?
'Gaeilge' is used as a generic term for Irish. (Scottish/Scots) Gaelic is referred to as 'Gaeilge na hAlban'. Similarly, Manx is 'Gaeilge Mhanann'.
I believe so.