Whether anyone finds Morris dancing silly is neither here nor there. If you're in the right frame of mind (and herbal refreshment!) most forms of dancing can look silly.

And Morris dancing does date more slowly than the other forms of "dancing" which the British have indulged in over the past few decades under the guise of fashion. Look at the dancing that you come across from time to time in 60s films; how many of us can look at that without chuckling?

I find the Gulf Arab sword dance extremely silly, but that's just me. I'd never suggest for one minute that they stop doing it just because I don't see much in it.