[Retra]

If all humans can be misguided, any principle which accounts for it will be universal. If someone else could know better than you, you can also account for that in a way that other people could be equally well served by.

So there isn't anything contradictory or inhibitory there. Perhaps you are not seeing the generality implied by the term "universal?" The contrapositive here is to not act in a way that assumes other people are incapable of, unworthy of, or disadvantaged by following your example. There is nothing here that implies one can't be humble or liberal. To put it in less gentle terms, the point is that if you don't intend for other people to emulate you, then there is no point to your life in human society.