It is not effective in extreme cases. Activists sometimes end up causing more pollution (traffic, garbage from protesters) or expensive damage to property or violence. Is is especially cringeworthy when protesters arrive at a rally wearing expensive imported apparel and gadgets made by slave wage laborers in countries contributing far more to world pollution problems.
Activists would gain more respect from their opponents if they were more willing to host open debates with their opponents. Even opponents want to hear good ideas on how we can work together without outright ruining the lives of people who are working hard just for their households to survive. I won't respect anyone forcing their opponents and allies to be silent, be late for work, or be fired while being forced to listen to repetitive angry chants. Saying something over and over doesn't make it more true, it drives people to follow or take the lead away from them.
Well said!