I agree that it's largely superfluous on webapps, but I would bet a crisp $20 bill that somewhere Airbnb is running a CMS-based site somewhere that loads jQuery.

I will rely on my nailgun v. hammer analogy for this again. I understand that the big scalable web experiences are built using nailguns. But for any sort of small web project that requires just a couple of dozen lines of code, jQuery is still very much implied.