I think most of The Great British Public are thick
Sadly, most of The Great British Public nowadays are immigrants or kin of..
Released 1969
Back then (late sixties, early seventies) the education system was constantly changed as well... remember, Hull had that phonetic spelling system introduced? We still see the results even now, although it wasn't
Steve's fault the schools failed him... nanny state indeed
So a mixture of new people and lack of education is the major culprit, I would say