It's the furniture...
Possibly.
I'm a baby boomer. I grew up surrounded by the M1. It was in every war movie. My GI Joe had an M1. The rifle was surrounded by nostalgia. And besides, in its own ugly duckling sort of way, it was/is beautiful and features lovely walnut furniture.
I grew up in the Vietnam era. The M16was on TV every evening. I was young enough that I had no idea of the teething problems with the rifle. When I went to get a high-power rifle to teach my boys, it was between a CMP
Garand and a newly built AR-15. I found a deal on a tack driver AR but it wasn't USGI and it didn't have the cache' of a Garand. Oh, the sight picture is better and it was probably more accurate, but it looked and felt like a confounded rocket. Has anyone come up with wooden furniture for the AR?
I think it is the furniture.
Well, I've got both now and can tell you the Garand is a young man's rifle: It's heavy. You need considerable upper body strength to hold it up for any length of time. But I love it. When you have one in your hands, you know you are holding a substantial weapon. I'm not sure that at 52 years old I'd want to schlep it all over a continent. From a purely weight standpoint, if I had to pack a single rifle now, I might want the AR. BUT, the Garand is a snap to clean. Because the AR "craps and feeds in the same place," it is a pain to clean. Other than that, it is very practical.
So perhaps, as an avocational shooter, I'm swayed by the furniture. But I like both of 'em.
In the case of competition shooting, perhaps what drives the bus is whoever is the hottest hotshot armorer just discharged from the Army or Marines.
Bob