For example, I'm using Debian, and I think we could learn a thing or two from Mint about how to make it "friendlier" for new users. I often see Mint recommended to new users, but rarely Debian, which has a goal to be "the universal operating system".
I also think we could learn website design from.. looks at notes ..everyone else.
My point is that 9front's user-unfriendliness is a feature (explicitly intended), whereas I think Debian's is a bug (not intended or desired). I'm not psychic, though, so I could be wrong about the Debian team's goals.