Yes, in Northern Ireland speech "folks" is something I'd associate with older, rural people, though I'm not immune from using it myself.
There's a definite thing in white American left wing circles of appropriating black modes of speech, hence the pervasive "folks" (and worse, "y'all"). What they don't seem to realise is that lots of African American speech is really Deep South speech transferred to cities across the country.
Hence the social justice subreddits full of very white people from very white cities like Portland or Madison who say things like "hi folks, I would like to know y'all's opinion on this" as if they were characters from Smokey and the Bandit.
Of course it's a thousand times cringier when white English social justice types copy the American style.