After a while, certain high usage routes will be noticed in the rideshare data. It will become obvious which streets and destinations could be optimally served with high capacity buses. Now is the time to bring in bus routes. Setup these bus routes and offer a discount for using them.
The current system isn't working, we need to try something different.
Jarett Walker writes well about this coverage vs. ridership tradeoff: https://humantransit.org/2018/02/basics-the-ridership-covera...
And I know rideshare has a bad reputation because of Uber/Lyft. But government can create rules they must follow to accept these funds. They can either accept those rules or some other company will. Or maybe a government rideshare service is a better option. This is a classic free market vs government service question and there's many options here. But the important point is allowing everyone to use rideshare as a transportation option.