Saying they are "responsible" for those things is like saying that a river is responsible for flowing or the Earth is responsible for rotating.
smack a leaf with the back of my hand
It is not the duty of plants to photosynthesize. It's just something they do. It is important to distinguish these two concepts, because if you equate them, then for example it is the duty of Exxon to destroy the environment. And this whole discussion presumes that humans and collections of humans like Exxon actually have a duty to not destroy the environment.
Well, this is a true statement. There is a meme "100 companies are responsible for climate change" which implies the companies could change their ways and customers don't have to do anything, but it's not true; we keep them around by buying oil and then we burn it.
The only way it could be different would if they could make carbon-neutral synfuels but it doesn't seem like this is happening.
However, it's not the whole extent. For example Exxon knowing about the CO2 greenhouse effect in 1982 and keeping quiet about that knowledge is problematic behavior that is not excused by customers' desire to buy fossil fuels IMHO.
I'm not wedded to the Exxon example. If you prefer, substitute any company that willfully breaks environmental protection laws to increase profits.
In America, most people cannot buy groceries without having access to a car. Car ownership is not required de jure, but it required de facto because of a lack of alternatives. America used to have transportation choice. Anywhere where there was transportation diversity, car, tire, oil companies bought out public transit and shut down the operations. On April 1974, San Francisco mayor and antitrust attorney Joseph Alioto testified that "General Motors and the automobile industry generally exhibit a kind of monopoly evil", adding that GM "has carried on a deliberate concerted action with the oil companies and tire companies...for the purpose of destroying a vital form of competition; namely, electric rapid transit .
Oil (and other) companies stimulate demand for their products. When consequences occur, the modus operandi of corporations is to shift blame to their customers. The concept of personal carbon footprints are the result of a PR campaign by British Petroleum .
I think the reason 100 companies is a meme is because it resonates. It feels right, but the counter arguments are convenient, easy. It resonates because it hints at phenomena that we can't see directly, but have tremendous influence on our lives.
I think in Carol Sanford's talks on living systems, the unique contribution a living system has for the ecosystem it lives within makes it non-displaceble.
Whether that should be recognized in our legal system, and something that helps humans participate in the ecology ... I don't know. The idea of legal personhood, at least, acknowledges that a living system is its own whole (if we are not just using it as a legal fiction), and it seems to me a stretch to say that a river "wants" legal representation. That sounds like the kind of stuff pre-modern tribal shamans do. That's not necessarily a bad thing in my book, but I don't know if our modern society is ready for that.
On the other hand, it could work as a balance to corporations having legal personhood.
No, those are not about responsibility. Is a river responsible for someone drowning in it?