Grossly inefficient personal transportation and industrial farming have massive externalities forcing people who want nothing to do with it to deal with it. That doesn't seem to be a concern that matters to most people. And they're exacerbating the same climate and energy issues.
Public blockchain can be powered by renewable energy, using its own value to pay for it, and can harness power in areas where it is not feasible to harness that power for other purposes.
Here's a podcast[1] episode with Saifedean Ammous, if you're interested in the value proposition. He claims Bitcoin actually saved his life, so obviously incredibly valuable to him. Lex does a pretty good job at pushing back on his evangelism.
