We must understand and explain what capitalism does and does not do, and can and cannot do about ecological destruction. Capitalism can promote development of more efficient solar, wind, hydro, etc. power (though this ability is tied to the price of the cheapest fossil fuel, and the relative abundance of coal means this ability will be quite limited for a long time) and battery and transmission efficiency. It may even be able to clean up certain continents and regions while polluting other continents and regions all the more heavily. However:

(a) Under capitalism, increases in efficiency tend to increase (rather than decrease) the consumption of a resource. This effect, known as the Jevons paradox, occurs because improved efficiency lowers the relative cost of using a resource, which tends to increase the quantity of the resource demanded, counteracting any savings from increased efficiency.

(b) Capitalism cannot solve the problem of reaching real sustainability*. It will always incentivize kicking the can down the road. This is because producing a product in a truly sustainable way is more expensive than producing it in a way that has an invisible-to-the-consumer environmental cost (such as using up a finite resource). Since, all things being equal, cheaper products that do the same thing will sell better, those who take the unsustainable route will undercut anyone trying to make things sustainably, drive them out of business, and take over their market share. The outcome will be a market full of actors none of whom will make truly sustainable products.

(* That is, actually being able to do it on an ongoing basis forever because no resources at all are being consumed at a rate that will ever exhaust them. That is what the word “sustainable” should actually mean.)

It’s not just a question of the greed of individuals, either. The system itself puts relentless pressure on anyone with decision-making power to promote short-term corporate profit at all costs. The corporations that make any attempt to conserve the world’s resources are outcompeted by those that willingly burn through them. Any CEOs who prioritize conservation tend to decrease a company’s profits and will soon be replaced by the board of directors with a CEO who keeps the greatest profits coming in. The politicians and government officials who refuse to do what corporate shareholders want are replaced by those who will. Countries and regions with laws that don’t favor corporate profit are starved of investment capital in favor of more corporate-friendly areas. Under capitalism, wealth is power, and the corporate shareholders rule the planet. Those who won’t promote profit for corporate shareholders are pushed out of power. Capitalism has no solution—can have no solution.

(c) Nor can it solve truly global problems like global warming and ocean acidification. The logic of competition-for-profit means that one company/country/region will always be incentivized to pollute to gain an advantage over its rivals (or just avoid being outcompeted and eaten by them). All actors on every scale are incentivized to cheat as long as their existence and well-being is endangered by others possibly cheating more than them. It is worthless for a world full of capitalist countries, each with its own capitalist bloc that must compete with all others, to sign a legal agreement to try to solve this problem. As long as competition-for-profit continues to play any role at all in large-scale economic activity, that legal agreement must inevitably be disobeyed by all actors.

(d) Only in a global political-economic system that is actually being run according to a single, unified plan (at least ecologically speaking) where literally everyone’s material standard of living is both guaranteed and tightly tied to everyone else’s can these problems be solved. If all would-be “cheaters” had to share the “profit” gained from contributing to global pollution with literally the rest of the people on the globe, there would be so little personal advantage to be gained from polluting extra as to not make it worth it.

Some further points are also important here:

One, the necessity of competition–which pervades every aspect of life in capitalist society–disposes us emotionally toward short-term, self-centered thinking and concerns. A democratically planned economy, in which everyone’s well-being is assured and no one is economically pressured to exploit or be exploited, will produce people who are inclined to be more generous in spirit toward all humanity (including humanity to come) and all of nature.

Two, in such a society, it will be clear that there’s no way for everyone to have privately owned cars and air travel. If the society is genuinely democratic, we’ll have to reach a way to satisfy those desires collectively, which will incline us toward things like less-polluting mass transit and other economic systems that are more sustainable.

Note:

Those who want to better understand why capitalism specifically behaves this way are strongly recommended to read the first five chapters of Zombie Capitalism.