Because a lot of folk music, (along with others) have lost their edge!.. and don't say much, anymore...so the folk artists just 're-package' the older styles, and topics, in which some just don't apply, like they did...but there's a lot of people regurgitating the past.
It doesn't have to be that way...I'd say, when you're writing...use the wisdom gained through the years, coupled with the exploratory nature of youth...and you might come up with something 'hot'. Speak to the common denominator of human emotions, but don't write lyrics that contain the word 'You' when addressing the listener. Nobody wants to be spoken 'down' to, as if you're turning them onto something 'new'....but if you say something that hits the 'common denominator', as per aforementioned, people's ears tend to perk up!

Oh, and unlike politics, don't address the LOWEST common denominator, of intelligence, but rather the most inside.....preferably the 'inside' (common denominator) that never gets spoken to!!!!

The Best To You,

GfS