You're avoiding the issue by framing the question in specific terms.
Please specify how, in this case, what is beneficial about the illegal operation of a taxi company for consumers (and taxi drivers) concerned about safety?
See what I did there?
I'm, not going to dig through the history of taxi regulation in the SF bay area to defend a point that is already made in law. Rape on women by unlicensed taxi operators has led to calls for mandatory police checks in the UK. Attacks on drivers in NZ led to the introduction of cameras in all taxis. So, forgive me thinking that ignoring the law as a basis for undercutting the competition is a shitty way to run a business.
There are already laws against violations of safety of passengers. If you really wanted to ensure passenger safety allow for concealed carry laws in the city, you'd have no issue with drivers harming passengers, or vice versa.
Not saying I necessary agree with the arguments. That said:
1. Never felt unsafe. Only time I've ever felt unsafe in a cab was mainland China which has less (enforced?) regulation.
3. Never happened to me in SF. Happened in Las Vegas (common thing where cab drivers take I-215 from airport to the Strip rather than surface streets); it's very easy to request a complete refund.
4. Public transit, bike, etc. Ensures that those who are really willing to pay for a cab get there quicker due to lower traffic congestion (theoretically - this probably only applies to areas dominated by cabs like Manhattan).
I wonder if it would lead to lower prices. Here in Sweden where basically anybody can start a taxi company the end result is that most companies a grouped within a couple of bucks of the two big taxi firms on the low end of scale plus a few companies charging two or even three times as much, and operating on the assumption that enough people (especially tourists who don't understand the taxi system) will simply jump into the first taxi they see without looking at the price. I've yet to see anyone trying to break into the market by significantly undercutting the big players.
Acting as though arguments for the common benefits of a competitive market should be dismissed unless the proponents are selflessly altruistic is an even bigger load of bollocks.
Nobody said anything about being noble or exempt from the law. The fact is the local laws are written by politicians that are in the pocket of the unions. And one doesn't have to be a noble knight to be opposed to this injustice and to realize it's just a legal extortion scheme.