The distinction between Skye and the Western Isles is interesting. I instinctively distinguish between Inner and Outer Hebrides, which I regard as strictly defined geographical areas. But my use of ‘Western Isles’ may be lazy, or wrong. In my minds eye, I do tend to include Skye in the Western Isles. Though curiously, I’d not include Mull. I cannot justify that.
A quick google suggests that the Western Isles normally means the Outer Hebrides, so my habit is almost certainly wrong. Friends back home, if I still had any, would be appalled. But none of the definitions found in Google look more than a couple of decades old, so I wonder, is there such a thing as an authoritative definition?
In any case, apols for confusion, my comments re Gaelic language and place names were intended to be pertinent to all of mainland Scotland, Inner and Outer Hebrides.
The one and only native bilingual fellow Scot I ever knew, from University days, came from Islay. I’ve never been sure about the pronunciation of that island, but seem to remember, he used ‘eye la’.