The maintainers of Bitcoin could make changes to the mining protocol that reduce its reliance on energy. By choosing to not do so, they are directly contributing - in a substantial way - to civilization-ending climate catastrophe. I do think that Bitcoin's maintainers have an obligation to do their part, considering that they are very materially a part of the problem.

Ethereum is at least working hard on other algorithms that are energy efficient. But in the Bitcoin space, the tremendous investment in energy-intensive mining equipment means that the entrenched players have an interest in persisting the way that things currently work, rather than seeking an energy conserving replacement.