If everyone changed their lifestyle the we would solve the climate crisis. It’s not like the big corporations release co2e because it’s fun, they do it because the people want the products (and they want them at a cheap price). Corporations are no angels by any means but they are directly downstream from the people.
It’s obviously more complicated than that but the idea that big corporations have the sole responsibility is just shifting the blame. You are still responsible for the portion that you put into the atmosphere.