The audience and actor are both important, as is the timescale. In the Faubus situation, it was a black student who went to school (actor) vs the general population (audience). The population was undoubtedly racist, and were generally unwilling to change their views. They had a general disdain for black people, and solving that issue had to be done quickly. The actor likely had no interest in changing the mind of the audience by himself, and the actor had a time-sensitive goal; going to school.
In the Davis situation, the actor, audience, and timescale are different. Far-right-wing radicalism preys on people who are shunned by society and tells them that they’re intrinsically better than members of society because of an immutable trait. To dismantle the radicalism from the outside in, one needs to directly challenge that ideology and be willing to put up with the abuse for a long time. Davis chose to face abuse over a long time period to push people away from a racist ideology; he was willing to suffer so that his goal of dismantling a racist structure over time was fulfilled.