I'm an admirer of Macca, but being honest: Who can say the performance wasn't embarrassing?
The embarrassement was enhanced by the the very unbritish accident, the failure in the sound system/mixing.
All Maccas big hits are incredibly demanding for the singer, and his voice just doesn't do anymore. He should be more selective and simply drop the tough ones from his set list.
Roger Daltrey is very much in the same situation. It's too painful to listen to ones idol and having to imagine how it
should sound. That's why I don't even consider going to the concerts of my biiig favourite Jethro Tull anymore.
Icons, yes, but to remain an icon and avoid becoming a target of "understanding" nods requires a timely retirement or a change of style. The artist needs to be able to change with his increasing limitations. That way he maintains dignity and true appreciation.