In my opinion, this is some fallacious bullshit. Consumerist culture did not spring up out of nowhere. It's a direct result of the variable the current capitalist system optimizes for - maximizing profit. It's a success story by these measurements. How is the author expecting for this change to happen when the system literally optimizes against it? Even if a cultural shift appears despite that, how long would it endure under the campaign against it that will inevitably occur due to the incentives in the system? Within the current capitalist system we don't even have the democratic power to effect any significant change to the system. Capital controls decisions in the corporation. Capital also controls a significant chunk of the democratic power in the political system. The only (somewhat) peaceful strategy that I'm aware of which has been shown to produce a significant enough counterbalance to capital that can affect political, economic and therefore environmental change is labor organization. Unions can provide the equivalent lobbying power to corporate lobbying, but on behalf of the majority. Of course it's also been shown that capital can destroy unions if labor organization isn't ubiquitous and robust enough. However that happens on the scale of decades which demonstrates the relative durability of the strategy.
TL;DR:
If you want to change the system in any meaningful way, away from consumerism, from profit maximization, from climate destruction, unionize and/or support the ones who can and do. A cultural change on individual basis that meaningfully affects the system is exceedingly unlikely if not impossible in the long run.