Earlier quoted context omitted.
This is a complete fallacy. Any black market, by definition, will have a higher incidence of other criminal activity, because people who are willing to violate one law are often willing to violate others. This is no different than arguing that we should continue drug prohibition because there are a lot of violent incidents that occur during transactions. That violence exists precisely because the activity was forced…
Here in London, unlicensed cabs are often as or more expensive than the regulated ones. So, please explain how this helped your "poor people" to get taxis?
Cracking down on these unlicensed cabs won't hurt the wealthy as much, who naturally have more choices for transportation, but it could absolutely hurt poorer people who have don't have as many alternatives.