That's true but the key word is coordinated. Without coordinated action, we're back at individual action. Coordinated action might be protests, boycotts, etc. Usually there are one or more _institutions_, that is a cohesive group of people, backing and advancing the interests of the group. This is a very powerful model.

A familiar example is the NRA. It's not a political party, but it advances the interests of its members relentlessly. Institutions of the left include things like Planned Parenthood. Often, there are issue advocacy organizations that spring up when corporations are doing bad things. Often the strategy is to do things that impact the corporation financially, which short of legal threats is basically the only thing they understand. Anything short of that can be brushed off with rationalizations by various powerful stakeholders within the corporation.

Basically, the point I'm trying to make is that individual action is essential, but not sufficient to make a difference when it counts.