Lots of taxi drivers are owner-operators, and many others lease medallions/vehicles but otherwise do their own thing.
As for taking the most efficient route, a driver purposely taking a longer route you didn't ask for to scam you out of your money is just that, a scam. So it's illegal on that basis alone.
They key difference with a lot of these taxi restrictions is they are set by the government to protect consumers. The government imposing uniform standards on taxi drivers through legislation is not at all the same thing as private companies doing so on drivers while weaseling out of employment requirements. The government can set lots of restrictions on how jobs are done without requiring employment contracts with those workers; private companies do not have those same powers. Hell, the government can execute people; there's no expected parity here whatsoever.
As for taking the most efficient route, a driver purposely taking a longer route you didn't ask for to scam you out of your money is just that, a scam. So it's illegal on that basis alone.
They key difference with a lot of these taxi restrictions is they are set by the government to protect consumers. The government imposing uniform standards on taxi drivers through legislation is not at all the same thing as private companies doing so on drivers while weaseling out of employment requirements. The government can set lots of restrictions on how jobs are done without requiring employment contracts with those workers; private companies do not have those same powers. Hell, the government can execute people; there's no expected parity here whatsoever.