Isn't it a bit like comparing apples and oranges when lining Tommy Steele, Brucie, Rod Stewart et al up against David Attenborough and John Humphries?
There are those who are there to entertain us, which takes a huge amount of stamina and charisma. The Attenboroughs and Humphries are there to inform us, and while this requires an agile mind and a pleasant voice, they don't have to keep up the physical presence, endless grinning and sparkle for hours non-stop.
Hving said that, Humphrey Lyttleton certainly had all his peers' admiration on to a great age, and certainly knew how to entertain. As does Nicholas Parsons.
We saw Elton John a while back. I had been given the ticket as a present for my birthday, so, although I was not mad about going, we went anyway. He put up a really good show and I'm glad I went in the end. Ditto Chris de Burgh - I only went to placate my husband, was rather embarrassed to be seen there, but the show was really good.
Mind you, the Elton John tickets, now I think about it, I got for my 50th birthday, so it was over 10 years ago now!