[WillPS]

Seems surprising some of the stuff that was able to get U ratings in the past. Conversely though, it seems to be increasingly difficult to get an 18 rating these days, you can fill something with repeated f bombs and strong violence and quite often get away with a 15 now.

I remember reading how the MPAA in the US will barely ever give a G (equivalent of U) rating to live action films any more, no matter how mild the content. Wheres over here it's not particularly uncommon for live action films, even ones not aimed at kids, to be rated U.

This topic is drifting pretty majorly away from Network at this point - but worth remembering that Animals of Farthing Wood was a children's programme, which aired on Children's' BBC for years. I can entirely see the rationale for a U rating. 

Attitudes change over the years, and not all in one direction either.