True cars and trains are loud. However, we're on the verge of both Caltrain and car electrification, which will significantly reduce ambient noise.

I can't believe we haven't cut & covered the Caltrain line yet. I imagine that's a project even the plentiful peninsula NIMBYs could get behind.

As sibling points out, airplanes at moffett are rather far away, whereas these flying bikes are meant to be point-to-point in dense environments. Also note that there's lots of regs & techs that help reduce noise for larger planes, and I'm not sure the same is going to be true for these smaller vehicles, similar to how all those two-stroke lawnmower and leaf blower engines are horrible both environmentally and noise-wise because they're optimized for size.