C'mon now, you can't very start calling things whatever you want. From the very first sentence of the description:
Taking our love of riding drop bar bikes off-road to its logical conclusion, we present you with the Gorilla Monsoon.
It's a drop bar mountain bike, it's not called that because that term kills sales. As does the term "monster cross". I'm not being a pedant here, if you walked into any shop and asked for a road bike that could fit 2.4" knobbies and run a 73mm bb the guys or gals there are going to give you a hard time. Bikes are categorized not only for what they're for but what design cues and features they exhibit.
And, tapered headtubes and forks have become more commonplace mainly because it is an added feature for both marketing as well as OEM production houses.