who knicknamed the bbc aunty ?

[Nutsters-Vex]

According to Guardian see first link below.
In the early years of its development ( BBC Incorporated ) the administrators were largely of middle class origins and demonstrated daily that they knew what was best for listeners and later on the viewers.This was derided by critics as the "Auntie knows best" syndrome. Hence the shortened version of "Auntie".
Patronising, much.