As someone who is broadly centre left in outlook, I do actually agree that there is some truth to this. From what I've seen, many environmental campaigners do talk in terms of complete economic and political transformation. And they are often conflate environmental issues with other issues of social and economic justice, even when the actual links between them is questionable. For example, do we have to solve issues of gender, racial, and income inequality in order to stop climate change?
Personally, I think that these issues are not inextricably linked. I'd like to see improvements in all of them. But I also think that climate change is a more pressing issue, because while human-scale problems can always be fixed with more time, runaway climate change is likely a one way process, and one with a very narrow window of opportunity to address. I think many environmental campaigns would find a more receptive audience amongst conservatives if they focused more narrowly on the specific issues of pollution and climate change.
Of course, campaigners do have a answer for this. They argue that these issues are inextricably linked. That the capitalist system is incorrigibly rapacious, and all these different problems are really just products of the underlying dysfunction, and cannot be tackled in isolation. That "evolutionary" improvement is simply an emollient that cannot address the fundamentally catastrophic impact of the free market and the global supply chain on the biosphere, and as such, revolutionary change, even though very difficult, is the only solution that can work, and therefore the only thing worth campaigning for.
My take is that, while some of the fundamentals of modern capitalism are basically broken, with respect to environmental impact, they are still delivering results, in terms of general reduction of overall poverty and improvements to quality of life for the very poorest, and security for the richest. As such, it's not realistic to expect to achieve major changes through campaigns focused on policy. Instead, campaigns to influence policy should focus on specific issues that mitigate the worst of climate change and pollution. Their purpose should be to buy us enough time as a species to solve the other problems using technology. Technological change can deliver genuinely transformative changes to the economy, as we're seeing with the adoption of renewable energy and electric vehicles, but not always fast enough.