I think that this topic is interesting for two reasons: intellectual arrogance and quality of play.
Intellectual arrogance is something that this forum can be accused of at times. To pretend that anyone has this great wealth of knowledge (even the successful, professional architects) and experience and can no longer learn things, or chooses to not learn things, about courses, great and average, is hogwash. To then move to the greatness of the course as a barometer for how much can and cannot be learned, is myopic. One might judge "something learned" on a great course to be cooler or more radical than something learned on an average course.
(I'll share something I find myself doing on average courses. It might be named find a new par three. I tend to glance back, across or over at other green sites and ask myself, how great a par three would that be? True, it's not something new about the current course plan, but it is something new about golf course architecture, about a better or lesser angle for an approach or a recovery. It certainly helps pass the time on a lesser course and allows me to walk in the footsteps of architectural giants on greater courses. Remember that Volcano hole photo of the 6th at CCBuffalo that went viral on here a while back? Each time we have a match, I find myself tracing a circle around it, imagining the play from all points along the curve...it's a great intellectual exercise.)
The second point is quality of play. If you are no longer trying new shots (flyer, runner, punch under the wind, half shots with longer clubs), why are you playing the game? To be sociable? Go to a bar or a house of religion or a fitness club. If you don't golf to get better at golf, no matter your age or muscular restrictions, you're betraying the tenets of all founders of sport. Faster, Higher, Stronger...the motto of the Olympics.
Whether I play Delaware Park Meadows or Arrowhead next, I'll learn something new. Whether I play the same course every day for 100 years, I'll learn something new. If that describes a failed learner, we need more failed learners.