I never played the board game, but I played some of the Computer Games.
They do not always explain all the Backgrounds of all the groups
It was thanks to fan videos on Youtube that I was able to figure out all the details of the universe .
Ending fan films is a bad choice .
When you have a universe as complex as 40K , all banning fan films does is alienate people who might look at the games .
This is going to cost them in the long run.