There has definitely been an increase in the availability of "folk" music [ a totally meaningless and discredited term these days IMHO ], in and around Aberdeen since the 1970s / 1980s, especially instrumental sessions. The question of quality, competence and musicianship is something else entirely.
At a "singaround-style" music event I went to on Tuesday night, I had to put up with "Bus Stop" [ "The Hollies" ] sung unaccompanied, badly, and the theme from "Born Free".
I'm fairly certain that there are more "Folk Festivals" in Scotland now than there were in the 1980s.
I'm also fairly certain that there are fewer "Folk Clubs" in Scotland now than in the 1980s.
Where you could go to hear an evening of traditional Scottish music in Aberdeen on any given night, I could not tell you.
"Folk revival" ? What exactly is it that is being "revived" ?