Before the giant rock came down, it seemed ok for the Ancient Tomb people to wander around the mountain. Assuming the area wasn't completely deserted except for the Toaist across the way, I'm surprised they never met anyone else. Like Grannie Sun never took little XLN to buy groceries? Never taught her to cook? No one in the sect seemed to know how to cook except Yang Guo.
Glorification = early feminists
Are they even a sect? Even if we ignore the numbers, the name Ancient Tomb was given by outsiders, they themselves do not have a name for it.
LCY didn't even actually teach her maid and didn't really accepted her as a student. So even if one were to accept that Ancient Tomb is a sect (I don't) can you consider her as part of it?