Of course it matters what it is called .
If I see an ad.( in the UK ) for Country and Western ,Folk ,Old Timey Blue grass or whatever I want to know which ones I would like to attend .
If someone advertises an acoustic session , I might go in the knowledge that I could expect to hear any of those categories mentioned ,and probably including Beatles , John Denver , Buddy Holly and others (take your pick ),but Folk would be probably any song which has been sang in Folk clubs since the revival, which, is a fairly wide church.
If we don't have singer songwriters in Folk clubs we may as well disappear up our own backsides.