Yes.
Protesting won women the vote, liberated India from the British Raj, ended the Vietnam War, has saved numerous forests and rivers from destruction, has helped improve the safety and rights of animals, has won gays the right to marry and freedom from persecution in some parts of the world...
There's an enormously long list of reforms that demonstrations have won.
History will remain what it is, but will also be revised whenever new evidence is found - and understanding history is vital to understanding why and how our society is as it is now.
Statues of victors don't simply mark facts of history; they also glorify the values of the rulers of that time, and the values of the winners.
Some old values, like slavery, do not deserve to continue to be glorified in any way. They would still have a legitimate place in a historical museum.
Such symbols in public places tell the oppressed that the authorities and systems of government ensure that their lives matter less.
If you doubt this, consider, would you wish to see statues of Hitler, Pol Pot, Idi Amin, Kublai Khan or Mao Tse Tung in your public environment?
