Just like any sufficiently complex program inevitably grows to have both a reimplementation of Lisp and a homegrown email client... any sufficiently complex library inevitably grows to have people arguing about whether it deserves the term language or not!

EDIT: I wish I were smart enough to have come up with these references, but I'm entirely riffing on https://en.wikipedia.org/wiki/Greenspun%27s_tenth_rule and https://en.wikipedia.org/wiki/Jamie_Zawinski#Zawinski's_Law . I can say from personal experience that both adages are resoundingly true.