It's bullshit.
"Boycott" comes from the last name of Charles Boycott. Protesters threatened and beat up people that worked with him, threatened shops not to sell to him, and ramped up to such a point that it cost more for the police to defend his harvest than the harvest was worth. His blacksmith was threatened with murder, and a 12 year old carrying his mail was threatened not to keep doing it. It was definitely not a polite "Oh, we don't buy from this particular guy" stand.
Now I'm not saying that threatening people is a good thing. What I am saying is that this narrative of that once upon a time people were civilized and suddenly this new "cancel culture" thing get everything out of whack is fiction. If anything, the past was a scarier and a rougher place, because if somebody stopped you in the middle of a rural road and threatened you, there were no cameras and no recording devices.