Profitable for who? The one hosting it foots the bill. If it was federated, all drivers could host their own instance like WordPress and a single app would connect to all instances and all drivers.
Agencies could start up to manage the tech for a negotiable fee if the drivers in the area didn’t want to bother with the tech.
Whether or not it could be profitable entirely depends on the hosting and delivery model. One guy could host the tech stack and charge maintenance fees and be in the green.
If you mean rich, then yeah, nobody would probably be rich. But you can build a small business as a hosting provider no problem, and the drivers would probably get a better deal. Uber employs so many people it requires they charge money. There’s a tipping point when the service provider becomes so large that their sheer operating expenses start to necessitate increased costs. Breaking up provides better value in that case.
You can - the software would have to hook into a background check service. This can absolutely be done.