To me requiring a special kind of driver's license to transport passengers makes a fair amount of sense iff it's reasonably easy to get.
Uber doesn't require that for UberX, which is the main point of conflict in many of the trials Uber lost over here.
Class A license - certified to drive tractor-trailer trucks.
Class B license - certification to drive non-tractor trailer multi-axle vehicles; kind of an amorphous collection, but think buses, large commercial panel trucks, dump-trucks, highway plow trucks, etc.
Class C license - any kind of normal passenger automobile.
What I find interesting about Uber, and the backlash against it, is that it is largely just a scaling of under-the-table, unregulated behavior people have always indulged in. What, really, is the difference between calling up your circle of friends and acquaintances, asking for a lift somewhere, and throwing them some cash for gas money and their time, versus using Uber? They are evil because they enable you to search a wider network then just your personal circle? Or because they take a cut for providing a reliable, safe, centralized payment service? Or because they have enabled a market that competes with a rent-capturing incumbent, and the product they provide is cheaper, more convenient, and higher quality?
With that said, I have to nitpick a few things:
1) This is a problem in many U.S. cities besides SF.
2) Uber has also shown a bizarre reluctance to deal with advance, regular booking. One employee even insisted that it would be anathema to Uber and against everything they stand for. Even though it would a) be trivial to implement, b) let them know of hails sooner, and c) give them greater knowledge of request patterns.
No, not making this up: https://www.quora.com/Why-doesnt-Uber-allow-customers-to-pre...
By law, I still have to use a taxi when returning from the airport here in Seattle (as opposed to Uber). I have had perhaps 2-3 positive experiences, some neutral ones, and many bad experiences with rude taxi drivers on their phones who drove erratically and tried to scam me with overlong routes.
And up until Uber and others arrived, they would either try to make me feel like shit for paying with a card, lie to me about it not working, or they would use carbon paper card readers circa 1985. Uber forced them to modernize in that respect, at least.
I badly broke my leg and, because I lived too far from public transportation to crutch over, had to take taxis to work 4-5 times a week, often both ways. No taxi company in sf will reliably come, even if you make it clear that you are going to take a cab at least 4 days a week for most of the next year. Instead, even when you are in the middle of the mission in a relatively dense location and going to soma, dispatch simply lies and says "10 to 15 minutes". A 95% wait time was 3 hours, and a 85% time was 1 hour 15 minutes, for what should be an approximately 15 minute drive. Even simple requests like calling a couple minutes before the taxi arrives so I could get down 2 flights of stairs on crutches without detaining the driver or having the driver leave couldn't be followed. Needless to say, this causes significant disruption to your life when you have to leave 90 minutes plus the length of the drive before going somewhere if you want to have any hope of reliably getting there on time. And god forbid you have to see your surgeon or something else with a hard deadline. The taxi services should be ashamed of themselves, and frankly participated in a violation of my civil rights as done by a quasi-governmental monopoly. And there are other issues: when I would occasionally have to pay with a card, the meter would suddenly be broken until you made it clear drivers had two choices: call the card in or not get paid. A fucking miracle would occur, and the card reader would start working. The taxi system literally shat on their customers.
The advantage of uber is simple: when requested, they either come, or say they won't. That allows you to be an adult and either make alternative arrangements or tell the other party you'll be late. I used uber even when they cost 2x as much as a cab just for this reason.
In conclusion, fuck taxis. Also, fuck sf. Only in sf is "a taxi that comes" a disruptive service.