Uggs are still way popular, and this idea of "leather riding boots" replacing warm-sheep-skin boots is a farce in your imagination, imo! I know, b/c I see the sales, almost daily! Cold leather riding boots are ZERO substitute for, warmth-loving sheep-skin! In fact, I'm wearing my toasty Ugg men's slippers as I type! I've owned "plain leather slippers" before, even some with faux fur, but I wouldn't trade my Uggs for anything else out there I can think of, for this time of year!
I'm not a "pom-pom cheerleader of companies I invest", so I won't attempt to rebut your other points, b/c some may be valid! But I will say, your notion that "Uggs is a fad that's over", especially for knee-high, leather boots", is comically WRONG, imo! No personal offense btw...
Also, to other posters making predictions, assume the worst always, and if you are proven wrong, then you'll be happy! Nothing worst than overly-rosy predictions about trading stocks, horse-racing and weather prognostications!