That seems to be the real issue here. D&D isn't designed to have the player control or decide anything outside of their PC's thoughts and actions. That makes the background features, as you interpret them, a clear outlier from the rest of the game. Therefore people who don't want to go against the core D&D constructs of the DM being fully responsible for the world, the players being fully responsible for their characters ignore or alter the background features.
Even though it goes against the assumptions of the game system you can, of course, have collaborative world building in D&D if you want. Personally, I don't unless it's discussions that happen outside of game time and even then I retain editorial control.