Does it mean I like the Gaelic (of this person/region)? Or is it about liking the language in general? Would it be wrong to say in the latter sense: Is toil leam Gàidhlig?
With 3 months perspective, I would say that it means "the Gaelic" in general. Idiomatic.
Hmm. A couple of exercises later I came across just Gàidhlig, so am becoming inclined that a' Gàidhlig refers to its specific variety/ability.
I thought it might mean "the Gaelic" people, or Gaelic-ness itself as a thing