They did one UK show of what like 40k after a while off and it didn't sell out.
Other stage headliners have massively stepped up recently sales wise - often they have a stadium show.
They could do WH or Other, I think other is more likely but its not 'easily' anymore. Maybe 'easily' in that they are aligned well with glasto and have good history with them, but size wise not so much.
IF they did WH it would definitely be very well attended, as would other.
Yep. Real Music bores would have found Elton appealing enough to go along with, but could probably be persuaded away from Taylor by some solid meat and potatoes slodge.