Fair enough. I am certainly not one of those who says that that Sixties icons should retire to a home for rock gentlefolk. There's nothing more boring and fatuous than adding up the ages of the Rolling Stones. If they can attract hundreds of thousands of people to rock concerts and give exhilarating shows then let them keep going. McCartney and Dylan also continue to give memorable concerts. It is not the live performance aspect that is a problem.
The curiosity for me is that the Sixties icons have lost some of their gift for songwriting. As The Independent's rock critic pointed out in his review yesterday, McCartney's album has hardly any tunes and forgettable lyrics. The Stones' album is cheered, only because it is of a reasonable standard, but no one can name a single song from it, let alone sing along to one. Dylan's gets raves, but then it is an album of bootleg recordings from the Sixties.
The truth is that the ageing process in rock stars does not particularly affect live performance, even though that is what is always wrongly seized upon. But, more than in any other art form, it does seem to affect the writing and composition. Bob Dylan's recent albums have been worthy with the very occasional stand-out track. But how amazed would the world be if "Mr Tambourine Man" or "Like a Rolling Stone" was released now. They are from a different planet. Paul McCartney has written nothing remotely comparable to "Penny Lane" or "Eleanor Rigby" for decades. If the new Stones album contained a "Street Fighting Man", jaws would drop.
But why can't it happen? These are the same people with the same talent. I put the point to Pete Townshend and Roger Daltrey when I met them a while back. Daltrey seemed to agree, saying that Townshend could yet be the great chronicler of middle-aged angst. We shall see if that is the case when a new Who album is released shortly. Townshend told me that the great pop songs of the Sixties relied a lot on "youthful energy". Somehow, that's not quite good enough as an explanation. Verdi retained his talent for composition long after the youthful energy had worn off; Arthur Miller's later plays never quite matched his great early period, but always repaid study; choreographers and film directors as often as not improve with age.
It is in pop and rock that things seem to take a wrong turn with the onset of middle age. Elton John's last album was something of a return to form. He said that he had sat down and had a long think and admitted to himself that nothing he had done in the past 30 years or so had matched the songs of his vintage period of 1970-76. It was a painful admission to have to make to himself, but it meant that he made an extra effort with the new one.
Perhaps, before their next albums, McCartney, Jagger and Dylan, should listen to one of their vintage works and not only try to match it but also try to work out why rock composers lose their way. I don't know the answer either. But this slightly eerie echo of the Sixties provides evidence that rock composers lose it at far too young an age.
It is reported this week that Andrew Lloyd Webber is considering the 20-year-old movie actress Scarlett Johansson for the role of Maria in his stage production of The Sound of Music in the West End next year.
Miss Johansson is as assured as she is attractive. But this could be a risky venture. She's a little young (Julie Andrews was 28 when she played the role on film), but that might not be too big a handicap. She's a little too sexy for the wholesome ex-nun. But perhaps she can play that down.
No, the real problem could be that for years now The Sound of Music has been screened as a singalong musical, often at gay fests, and often with audiences in costume. Will Miss Johansson be able to cope with seeing images of herself in the stalls, singing her words with gusto? Has Lloyd Webber warned her: "Don't worry about the nuns in the audience. They are just musical aficionados in drag."
It might be a bit much for a 20-year-old. But good luck, Scarlett. Climb every mountain.
* A cultural quiz question which will normally stump the most avid arts aficionado is "Who is the opposition culture spokesman?". Give up? It's Theresa May. I knew that, but I confess I didn't know until I saw it flashed up on TV the other day what her actual title was. She is, in fact, the Conservative Party spokeswoman on Family and Culture. Ah, that all too telling word "and". You never find frontbench spokesmen for something and health or something and education or something and defence. But culture? That can happily be a second strand to a portfolio.
The arts world should point out to the next leader of the Conservative Party that the nation's culture is important enough to have a portfolio all to itself. As a second strand it gets quietly forgotten. I have seen Theresa May pontificating on family issues. I can't recall any major statement from her about culture.