Most common is fare scams (driving in circles, pricing scams and various types of extortion), assault and sexual assault.
Then you have things like all the types of discrimination you can think of as well as safety issues (having seatbelts, having tires with tread on them) and so on.
Fare scams still occur on metered taxis, and these scams are any more widespread in taxis than any other industry.
Nothing distinguishes transportation, from say, overpriced crappy old model cameras on Fisherman's Warf, Dead Sea cosmetics, or any other scam - other than that it's easy for the city to claim it needs to regulate.
A simple licensing and complaint system is all that is necessary.
These things don't occur in a vacuum. Taxi's are more highly regulated because people demanded that "somebody do something" because things were pretty bad.
I definitely agree a better regulatory system is possible but pretending it would be easy or simple is silly.
A simple licensing and complaint system is all that is necessary.
That doesn't work very well for tourists, who are the most likely to be scammed, and whose money is highly desirable as it represents an input to the local economy.
And regardless, creating a communist style fixed price centrally managed system is not the solution to tourists being scammed. It doesn't solve the problem, raises prices, and limits supply - it's a lose lose for everyone (except monopolists and city hall).
The regulatory framework is outdated and unnecessary.
You don't really have enough insight into this (apart from "regulation bad") to continue the argument. Taxis work fine in a lot of places, there's a reason for their regulation, and that's fine.
Uber is a private car service. That's what they should stick to. Taking on taxis on multiple fronts (different cities, states, countries) is a losing (and, quite frankly, boring) proposition.
The problem, in this case, is attempting to apply SF-sourced corporatism-as-libertarianism to places other than SF. Good luck with that (and I say this as a person who uses Uber as my sole method of transportation, several times a week).
New Yorkers disagree. New York's medallion system has resulted in a world class taxi ecosystem. There are other examples as well. Are there examples of equally good taxi ecosystems in cities without regulation? Or examples of negative consequences which outweigh the good but are not generally accounted for?
Evidence based arguments trump ideological arguments. You saying "it's a lose lose" or throwing the word "communist" in there doesn't tell me anything other than that I might be entering a religious argument instead of a reality based discussion.
The problem with heavy government involvement in any industry is not that it's inherently bad, but that if it is bad, it is very, very hard to change. With minimal good regulation on transparency and accountability (I did not say no regulation,) consumers can quickly vet good providers.
New York is lucky in that it has reasonably good regulation on taxis, though far from perfect - there are many underserved areas for which there is no incentive for taxis to service, and where it is illegal for other parties to service. Along with service at peak times, New York would benefit from eliminating the medallion system and instituting a simple regulatory framework where anyone with appropriate training and licensing can provide taxi service.
Uber is an example of good quality taxi service without (or circumventing) regulation, as is Lyft and the other startups. The negative consequences are obvious simply by looking at the market opportunity and demand for fixes to the broken taxi system. San Francisco suffers from insufficient taxis and an inability to adapt to demand.
The purpose of the regulations has become primarily to protect taxi unions and companies by limiting supply, not to promote safety or prevent fraud.
Perhaps you should offer some evidence to support that assertion. By definition, a tourist is only around temporarily, whereas a complaint can take a long time to process. If a tourist has a bad experience, they're unlikely to return.
Then you have things like all the types of discrimination you can think of as well as safety issues (having seatbelts, having tires with tread on them) and so on.