To be honest it depends on my mood if I wave or not and the amount of friendly nods/waves I have received.
It's a rapidly changing world with more people too cool to acknowledge other riders.
Alot of the time when the weather is hot I wear a bandana or neoprene face gaurd so as not to get wind burn/sun burn , when I just ride with my grey beard showing I will notice other grey beards . The sports bike riders with full face helmets will occassionally nod.
I think it's dying out gradually except maybe on remote sections of road.
