Why? simple, contrast.
The values that Df expresses are not bad but they have a problem, in an expansion like this, which feels so unthreatening and with such a bright atmosphere, the value of these messages feels little impactful and the constant emphasis on it makes even It can be tedious and tiring, it feels like the norm of the world, something mundane.
Love, Family, Courage, Honor, Friendship, etc. feels more important when contrasted with a darker and more practical world.
A parent giving her life to protect her child. Or a lover crossing a battlefield in search of his beloved.
A younger taking responsibility for his young brother or half-brother after he was orphaned, or an orphan taking care of an old soldier who rescued him and raised him as if he were his son after a war.
One or two youngers taking up arms for the first time and attacking some kobols who have come out of the nearby mines and started looting, or a group of ordinary people defending each other from armed repression.
The story of Eitrigg and Tyrion is a great example of honor and maybe even friendship later.
I am sure that many can give a better example, the point is that just as death is necessary for life to have value, “darkness” is necessary for good values to matter, the contrast is necessary.
Unfortunately there is not much contrast in Df, the fact that the ingame story has been so poorly presented in some points and even important information cut out and put in books does not help, and saying that Df is a luminous counterbalance to SL doesn’t help much either since it could have been good at the beginning but it has been extended for too long.
Personally Df seems like a laboratory experiment, as if it were done in a vacuum, disconnected from the average world. I have hope for the World Soul Saga, but for it to be truly successful I think it should have more contrasts than Df, be darker.