I agree that a open car concept would be hard to bootstrap. It wouldn't surprise me if we're talking about $3-4bn to get to where it becomes a pure manufacturin

I agree that a open car concept would be hard to bootstrap. It wouldn't surprise me if we're talking about $3-4bn to get to where it becomes a pure manufacturing problem and evolution can drive itself. That is, you just need to be able to prove that the critical parts someone manufactures are within spec. If I had that kind of money lying around I'd probably initially focus on funding projects in academia in collaboration with regulatory and certification bodies. There are already (largely pointless) academic programs to design and build race cars. It should be possible to interest academia in doing something vaguely productive instead. Like collaborating on designing a platform for cheap mobility. As for simplicity and scale: simplicity is absolutely a requirement for cost efficient scalability. To see how incredibly important this across disciplines, have a peek at "How Big Things Get Done" by Bent Flyvbjerg.