] What happened? I have two vague speculations. The first is that the French Revolution warned aristocrats world wide that it might not be a good idea to parade your wealth overmuch. The second is that it was the restraining influence of Beau Brummell, who considered that a gentleman should not attract attention by his clothing.

I suspect that the French Revolution may have been an influence, but I would also wonder about the effects of the Napoleonic Wars on fashion. Being too showy in a time of war has been often frowned upon. Of course, this too is just speculation.

BTW, I may have missed something, and I'm leary of parading some ignorance, but who is Beau Brummell?