Boycotts don’t work for one reason...I still need to brush my teeth.
You are going to find that every major brand of every major commodity advertises on every major network every day. There have been boycott promotional companies for years now and they have little effect because people still need to wash their clothes. They have had “outrage” of the week promotions so often that it’s hard to keep up.
The only way to be effective would put these boycott promotional companies out of business. They would have to compile the worst offenders in the media (1 to 10) and target only one or two companies at a time. The problem is that unless there is a daily outrage, no one will send in donations.
I can think of several direct mail marketing companies that sell toothpaste.