So I went back to the original PDF,
https://b8f65cb373b1b7b15feb-c70d8ead6ced550b4d987d7c03fcdd1..., to look at the list.
I see lots of companies that sell oil there. Or coal. Or things. But none that really emit pollution as a side effect.
Someone like 3M could pollute less by changing the way it produces each packet of yellow stickers. The pollution is a side effect, it's something the company can change by internal decisions.
Someone like Shell cannot pollute less by selling 1l of petroleum (I assume that pollution during production is a rounding error in this context). The pollution is inherent in the product sold. The act of polluting is identical with the act of selling.
Which implies that your last sentence should be "the most we can do is stop buying polluting products".