Do you have any sources you can cite on point one? I can see that there could be a reasonable hypothesis that centralised services will reduce costs for drivers

Do you have any sources you can cite on point one? I can see that there could be a reasonable hypothesis that centralised services will reduce costs for drivers heading to pick up customers, or carbon emissions, both due to shorter journeys. What I'd be interested in is whether or not that has been studied, how variable the gains are by locale (eg big city, small city, town, etc) and what the consequences are for driver pay and conditions. Likewise, effects on things like price paid per journey, both average and 95th percentile so as to gather peak pricing (which, in the UK at least, cabs don't charge). It'd also be interesting to understand why this isn't done on a municipal level - eg, a unit of local government could buy one of the many, many off the shelf systems for this and require taxis to use it. Perhaps a few tweaks to make it multi tenant, so as to preserve the existing structures of taxi companies. I suspect this would confer the benefits of more efficient allocation, without the ill effects associated with Uberisation.