I am extremely sceptical of Musk in general, and what seems to me a Utopian vision founded on tax rebates for his cars. HOWEVER. The basic idea of the Boring Company (which is a fantastic name) is, I think marvellous. Frome what I recall, he wants to build tunnels for this type of project basically 1/10 or 1/100th of what it now costs to do an underground train tunnel. I think it's amazing. I had no idea a proof of concept was in the works and that video makes me irrationally happy.
Well, the main "problem" with most tunnels these days is that they're too large. The larger they are, the more supports you need, the more reinforcement. You need them big if you're going to have enough air to keep passengers alive while running fossil fuel engines in them.
While I'm not sure that current government approval agencies are
capable of wrapping their heads around the idea that small-bore tunnels can be safe, from a technical standpoint
electric vehicles are far safer, not tending to produce carbon monoxide when slightly starved of oxygen.
Even a small gasoline engine gulps fare more O2 than a human. Eliminate the engines and you can have, as we see, far tighter tunnels, less ventilation, lower cost. As long as you're controlling the environment that much, ramp up the speed so that people actually want to take the tunnel because it's faster. More people in the tunnel(s) and that's less on the streets above.
While it may not be able to match the raw people-moving abilities of a subway, a 'sled' system that hauls your car along can be more useful on an individual level at far lower cost.
