The 1992 Earth Summit in Rio (where the United Nations Framework Convention on Climate Change was created) was a landmark year for the news reporting that climate change is by far the most important issue humans are facing. Widely seen news has been reporting scientists' warnings about the existential threat of our overpopulation and fossil fuel since then, and in the last 30 years the media has been reporting on it more and more every year.

falls onto a handful (or so) of very large corporations

Those companies are not burning the planet for the hell of it - they do it because billions of people choose to buy their biosphere destroying products and services.

While we should vote for Greens who'll make laws where anyone using more than 2.1 tonnes of CO2e per person per year is jailed, instead of for people and parties who subsidize overpopulation and fossil fuel use - in the short term that usually doesn't do anything unless a threshold is passed. Individual action (reducing our communities' fertility rate by 2 orders of magnitude for several decades, not flying, not driving, not living in unsustainable places, ...) while vanishingly small, does actually make a measurable difference.