I'm frequently annoyed by people who think the unsustainability of exponential growth is somehow specific to Bitcoin, and not the entire global financial system.

Global finance consumes a lot of energy and resources, and encourages businesses to harvest natural resources and find externalities to continue a compounding growth rate. It is mathematically impossible for this to continue unabated on a planet with a fixed amount of resources. Eventually, something will have to give. Hopefully markets will find a graceful solution, but the transition will probably be ugly.