So here’s an idea — the city of Seattle sets the following goals

1. All citizens in the city should be able to get downtown in 45 minutes or less during peak hours.
2. The cost of this ride should be no more than $5 (I just made that up)
3. This applies to disabled people as well.

To meet those goals, the city has an existing bus network. Expanding the bus network to other areas may not always be feasible for financial and logistical reasons. To fill in the gaps, contract with Uber / Lyft to guarantee a certain level of service via Hop / Line. Citizens pay the rate in #2, the city pays whatever agreed-upon surcharge.