In my personal experience, attending venues from the late '70s through to the late '90s, it seemed like you were surrounded by your peers, then suddenly a much older crowd appeared in the '00s, and the last few years has seen a much younger clientele coming onto the scene. This has led to as much as a 50 year age gap between the youngest and oldest attendees at some venues.
It doesn't seem to be a problem, with everybody on board for the love of the music, so I reckon it's a case of carry on regardless, as long as you're still up to it.