Buses don't require a lot of capital, which is why there are tech company shuttle buses and not tech company train lines. It would make sense to make public buses work better (more dedicated lanes, more expresses, and so on).

Also, tech companies are already outsourcing shuttles to contractors. Those contractors could run other lines if someone were willing to pay them.

If it made sense for the tech companies to pay the city to run buses then they probably would. The question is how to provide better service while serving the general public.

I wonder if a company like Uber would eventually start running buses?