I think he's saying that eventually we will run out of economically viable to extract resources and we should start planning for that now. I'm not quite so sure because there are still tons of people living in awful conditions and they need a lot of this resource extraction to raise their standard of living.
People here really misunderstand and misapply the concept of economically viable to extract.
As cheaper sources are exhausted, the more expensive ones become viable. So we won't run out on the projected time horizon.
The main reason why US and Australian rare earth production has gone away is because Chinese sources are so much cheaper (aka no pollution or safety regs). No production, no exploration, and no development of rare earth sources.
As cheap production goes away, people again look for, build, and use other sources.
Many people need this resources, including our children. That’s why we need to slow down our crave for things and enjoy what we have. We don’t need to change cars every 4 year, we don’t need to commute as we do, we don’t need all the clothes, we don’t need to eat meat at every meal. Also we don’t need to work in useless jobs only to have money to buy useless things. We need to reconnect with nature and with each other.
I agree that the consumption isn't sustainable long term. At the same time, consumption of clothes, food, household goods, etc. in rich countries helped China to lift hundreds of millions of people out of poverty by giving them better paying manufacturing jobs.
Resource extraction under capitalist, fascist or otherwise non socially minded governments has been shown to hinder growth in regions where high amounts of valuable natural resources are available since elites can leverage the low cost of labor to extract said resources.
Planning on a backup plan and providing large numbers of jobs through factories to increase the value of labor in these places is a much better way to increase the standard of living other without installing socialist governments.