Faolyn
(she/her)
if your argument that an optional rule tucked in the dmg is required to complete a poorly written background feature available to player characters in the PHB ho take the noble background, You'll get no argument. That doesn't change the fact that it looks like the blurb I quoted earlier looks to be a significant improvement worthy of praise for the apparent improvement.
Since NPCs are the domain of the DM anyway, it's rather supposed to be in the DMG.