Neuroscience and even brain-computer interfaces have indeed had decades of research and billions (though not hundreds of billions) in funding. As a partial proo

Neuroscience and even brain-computer interfaces have indeed had decades of research and billions (though not hundreds of billions) in funding. As a partial proof of concept, BCI's are already capable of multiple-degree-of-freedom control of prosthetics. And there just so happens to be a glut of PhDs and post-docs in the sciences looking for a way to apply their training. Of course it is true that Neuralink is a much larger leap from the current state of the art than mass production electric vehicles or reusable rocket stages. But is it a larger leap than a million people living on Mars? These ventures have many valuable milestones along the way, even if the ultimate goal proves unreachable.