They're talking about our nascent circular economy.

Recycling now recovers >95% of raw minerals (and will continue to improve).

The learning curves for battery and solar tech will more than make up the for the shortfall.

Meaning at some point in the near future (2050 IIRC), humanity will have mined all the lithium it'll ever need.

Also, in the same time frame, it'll be economical to mine our garbage dumps. Further reducing the need to extract raw materials.