Moral revolutions are typically seen retrospectively. Prospectively, the revolutionaries tend to look like crazy people, and sometimes they are.

Some philosophers have begun writing sympathetically about predator elimination as a way of reducing animal suffering. From an environmental perspective this is somewhere between naïve and potentially disastrous.

If you look globally you see a patchwork of jurisdictions (nations, states, provinces, cities) that have taken aggressive action on climate change, and a patchwork of jurisdictions that have not. These various policies reflect the politics of each jurisdiction and the values of its citizens.

It's possible that we'll screw up the climate so badly that most of us will die and a few breeding pairs will remain somewhere in the arctic. What's more likely is that we'll continue remaking the planet, driving many species to extinction, killing millions of people through the indirect effects of climate change, making life even harder for the poor and powerless than it is now, and making it a little more difficult for the global middle class to live the lives to which they have become accustomed - in other words, business as usual, only worse.

The most fundamental challenge of the anthropocene concerns agency. For those who lived the Enlightenment dream (always a minority but an influential one), agency was taken for granted. There were existential threats to agency (e.g., determinism) but philosophy mobilized to refute these threats (e.g., by defending libertarianism) or to defuse them (e.g., by showing that they were compatible with agency).

Bentham spent much of his life writing constitutions and proposing legal reform in the light of his utilitarianism. The evaluation of particular acts was hardly his concern. The psychology of his day was hedonistic and he worked in that framework and passed it on to Mill, but it is clear as day that Mill was not a hedonist in the sense in which we use that term today, though he used the language of pleasure and pain to express his views.

In trying to develop an impartial, expansive ethic we are trying to get ethical systems to do something which they did not evolve in order to do. This doesn't mean that it can't be done or that we shouldn't try to expand the reach of our ethical frameworks, only that there are reasons to be skeptical about its success.