A point of note: the phrase was popular in the climbing/skiing/snowboarding/mountain biking communities years and years before the frat boys appropriated it for activities mostly pertaining to drinking a lot and being a degenerate.

I'm sure that's true, while at the same time it could help answer some of what the parent was asking "Why am I hearing this term more and more?"

Full Send predates them by at least a decade. It’s a very short walk from “send it”, as in I’m going to send it, which has been part of that culture since at least 2000.

This term was used well before 2010... that person might have the trademark but it was used in extreme sports (e.g. skateboarding type events) since the 1990s.