I have the general impression that men are starting to get the message and playing shorter sets of tees. This comes from personal anecdotes, i.e., as a kid, my dad wouldn't play a course under 6,000 yards. Now, during master plans, etc., I find that seniors (you know, guys about my age) avoid playing tees over 5,999 yards, and seem to prefer 5,750 or so. They still balk at going under 5,000 yards!
Another anecdote which affected me....I was playing Pinehurst no. 2 with Rees Jones not long after his remodel there. When I went to the typical men's tees, he admonished me and said he was playing the senior tees (he is older than I) I moved up to be sociable, hit a lot of greens, and the lightbulb went on - golf is fun when hitting far more greens and fringes than not. And I still play at around 6,000 yards instead of 6,600+.
Side note, the top tracer tech at many driving ranges now probably contributes to more golfer depression cases than any other thing. Now, I know for a statistical fact my drives are only in the 216 yards range......and can only justify a few more yards based on the interior guts of the ball probably cost a few yards. At least, they don't sound great leaving the club, so I presume they are different.
Statistically, driving distance falls into six categories for men, and for all but the top distance range, are going down. Those seem to be about 295, 258, 216, 170-200 (broad range for senior men) and 140 for recreational females. BTW, those lower groups can hit further, but only do so about 20% of the time, complicating matters) BTW 2 - that 216 used to be 229 prior to about 2000.
The "typical" course yardages have been 7250, 6800, 6350, 5750, and <5000. If we make all tee distances proportional, so everyone is hitting about the same club as pros/scratch, those yardages would be 7250, 6340, 5308, 4669, and 3440. Basically, even the "A" players could stand to be playing a bit shorter, although I expect some to contest the idea that they should be hitting the same clubs as pros.
Another way to measure is multiples of tee shots. Say the scratch player is 25x tee shot distance (i.e. 300 yard drives and 7500 yard courses.) If we make that 26, 27, 28, and 29x drives for other levels of players, because hitting the same clubs seems like too much of a giveaway, it comes out to 7500, 6708, 5832, 5,320, 4,060. Any way I measure it, from the middle tees forward, courses are generally just too long.
I once wrote an article (actually 2 or 3) for Golf Course Industry along those lines, and was quoted in 2008 by the Wall Street Journal as saying "you course is too damn long!" I also noted the back tees should be "merely a rumor" to most players, etc. Short version, as a designer I tend to feel golfers can't play the "wrong tee" but that the tees they choose from are merely in the wrong place. Golf tradition keeps them where they were, but where they were was based on tradition, i.e. circular and flawed logic. With more stats in place, I think gca's need to do a better job of placing tees - and designing the holes - for shorter hitters, rather than design from the back tees and ignore other driving distances, while hoping for the best.