maybe, maybe not. could just be the mech noise an engine makes or could be from slight wear from use, could be both, could be getting worse, maybe not.
todays oils with high milage slider cams..
I run a 15w40 diesel oil from napa and let it rip. it had 75,000 miles on it,pulled,sat 3yrs,went back into service in 10' running the snot out of it.
I got to the point I had to stop worrying about the oil/slider cam/wear/noises/leaks and just get on with it.
fires right up, idles good cold, warms up fine, 200-300 mile trip with no troubles. gets 15 mpgs if i stay at 2000 rpm with the stock MH cam.