I wouldn't call transit systems "unbiased social good" in every case.

In many cities, bus systems have to strike a balance between frequency and coverage. My transit system had big plans to switch many routes to have straighter routing and fewer stops, while providing much better frequency and hours of service. This would have attracted more riders and increased funding for the system. But, local councilors were swayed by the idea that impoverished senior citizens relying on their milk run that comes every 45 minutes until 6 PM would no longer be near enough to a stop, and so not equitably served (never mind that we have a paratransit service for people who truly can't walk to a stop 500 metres away). So, nothing changed.

I'm not surprised that private services are going to fill the gaps here.