Re: So what the author is suggesting is...
Actually, a variant would word well in the countryside. City dwellers have the option of buses, light rail and taxis- or facilities are close enough to just walk or cycle to. Here in a smaller town, public transport is very poor.
The proposed system would allow young people (even those with driving licenses currently face crippling insurance premiums) to travel to the cinema in the next town, for example. (Only this morning, the local paper tells of a coroner's finding that two young men died in a car crash due to the driver speeding so as beat an 11 PM curfew imposed by his insurance company and enforced by a TomTom-manufactured GPS logger. )
In the UK, there have been trial schemes of a service akin to a bus/taxi hybrid... one rings up to with a request to travel from A to B, and you are contacted later with the time at which you can expect a minibus to turn up. The idea is to lump together people to make efficiencies in a time when local bus routes are being cut back. It was aimed at an older demographic, and before adoption of the smartphone (a GPS-equipped device can only aid services like this, if its users have the inclination and ability to use one).
In France, people who never gained a driving licence in the first place (usually the old) may drive a specific model of low powered car, limited to around 30 Mph. Sometimes they are bought by people who have lost their licence due to drink-driving. Also in France, I see that young people are allowed to take passengers on their mopeds.