I remember Frank Thomas -- he's the guy who told us all, back when driver clubheads were around 360 cc, that they had reached the point of diminishing returns and would not get any bigger.
Honestly, it would have been simple in my view to have done the right thing(s) -- limit clubhead size to about 300 cc, and give meaning to the Overall Distance Standard in USGA ball testing.
Metal clubheads themselves are not the enemy. If you've ever built or repaired clubs, you'd know that persimmon was a nightmare. It was like open-heart surgery to replace a shaft. Persimmon was inconsistent in use and in play. Some persimmon drivers were great and some were terrible. If not treated very carefully, they could swell if they got rained on. The sole plates fell out. The face inserts got loose. The whipping (remember whipping?) came loose. I remember the days, in the mid-seventies, when collectors were selling prime MacGregor Tommy Armour persimmon drivers for $500-$1000.
Metal clubheads have made the game more affordable, more accessible. All the things we want to promote in golf. That is not to say, however, that all is good with clubs. The USGA missed the boat on clubhead size regulations, and I don't think anyone bears more blame for that than Frank Thomas.
And sure; it practically goes without saying -- the ball is the one part of the game that ought to be easiest to regulate. It is the cheapest, least consequential, most fungible, most easily-replaced, least memorable part of the golfing experience. What other sports would fail to protect their most sacred venues in the face of a company wanting to make a ball that went faurther? Would baseball move the outfield walls at Fenway if somebody invented a farther-flying baseball? The problem is that it golf balls are such a huge profit centers for a few big corporations. And one in particular that wishes to protect its market share.
As for the folks who say, "No ordinary recreational golfers are obsoleting anything, be it Merion or Maidstone..." It's mostly true -- but only if bifurcation is acceptable to you (it isn't to me) can you say, "Let the tour players play with a special tournament ball if that is what is needed for them." That is another debate entirely; one in which I am happy to participate, but which is also one in which the battle lines get drawn very differently. Titliest, for example, which opposes a ball rollback as desperately as anyone on planet Earth, also strongly opposes bifurcation...
The fact that PGA Tour players' games are so different from that of average golfers, makes me less interested in PGA Tour golf, not more. But even many of the collegians I saw playing at Inverness this summer were rendering that course (a U.S. Open course!) obsolete...