Let's go through this one by one.

What about the rest of the civil rights movement? The struggle for civil rights involved dozens if not hundreds of groups both peaceful and violent, and all of them contributed to the eventual success/"success" of the movement. Also I should note that desegregation was gained via a court case, not (just) protest. For one prominent instance of violence in the civil rights movement, see: https://en.m.wikipedia.org/wiki/King_assassination_riots

Women's suffrage in America was for the most part peaceful, but it was also not something the elites had any reason to oppose. This is an apples to oranges comparison. In Britain, where the elites were more intent on resisting women's suffrage, things got pretty gnarly.

Ths Delano Grape Strike (not boycott) is not relevant due to the government not being involved one way or the other. Also note that the reason the strike remained mostly peaceful was because the (very much violent) labor rights movement had given them the right to not be shot by private militias. The violence necessary for the strike to succeed had simply been outsourced to the past.

Weren't we talking about American liberties here?

See above, but also the Indian independence movement was kickstarted by a violent uprising.