I think lampooning or parodying something like dance forms is probably as old as the dance forms themselves whether that be barn dance, country dance, ballet, military two-step, cajun or morris.

I remember the two Ronnies routine with morris dancers, very clever, very skillful and very entertaining. I don't think they were treating morris as a 'joke' in a ridiculing sort of way but they did make people laugh, created a lot of enjoyment for the dancers themselves and the viewers. Which i guess is what morris is all about.

I don't think morris is meant to be taken toooo seriously except by those who have to perfect their dance routines and moves. Tis there to tell a story or fable or depict a pageantry in music and dance.

As to the original question; i don't think morris dancing has ever been a joke ('cept of course to those who perceive it as such) but it is definately often very amusing and very entertaining both visually and musically and long may it continue!