I can't help wondering what would happen if all this money was invested in buses (both on-demand and scheduled to accommodate those in rural areas where it's arguably too expensive to have a regular schedule) and trains.

We have an ageing population globally, and given the delays/lack of scale /etc of autonomous shuttles and cars, there's going to be a whole lot of people prohibited from accessing in-person services and participating in daily life.

Hyperloop will not happen anytime soon, they are still in the R&D and partnerships phase by and large.