Anyone who is a Londoner will probably agree that after a while background noise becomes part of the scene and we tend to ignore it as we get on with our daily lives. Sirens wailing all the time, shouts about this or that, music coming out of shops, screechy brakes on vehicles, demonstrations, Hare Krishnas banging drums, etc. Most people have no time to stop and listen, we just pass on by.
Perhaps he needs to re invent himself and try something new. After such a long while, although his message may be sound, his delivery if it now has the opposite effect in a fast moving world.