You're right, and funnily enough, that's the same sort of advice that the article's author got. Start slow, focus on avoiding single-use waste, you can't do it all at once.

But that was an example, plastics are only one small part of the problem. Production of energy, metals, wood, food, etc. Disposal of the toxic byproducts. Nothing we do at a large scale is clean or sustainable, and there's almost no accountability for any of it. Individuals don't have the ability to meaningfully influence all of that, outside of large-scale political action.