In other markets, they did. Where I live you need to have an appropriate license to transport passengers for money. Hailo brought the app approach to hiring taxi drivers. Uber now exists here, but all the drivers are actual licensed taxi drivers charging the standard rates. They did briefly try to "disrupt" the market here by ignoring those rules, but they got slapped down.

In Austin, they had a taxi app at the right time. The problem was that they were still taxis, and if no one felt like ever coming to pick you up, then you were just left high and dry. Uber told a specific person to come pick me up. Taxis would take whatever fare they found on the way to my house.

Not quite. There was a post on here that Uber's other big advance was the fact they don't own taxis and via demand pricing they incentivize more people to drive during high demand times. A Taxi company can't do that. They can't afford to own enough cars and hire enough drivers to handle high demand times as they'd lose money. Just adding an app to taxis is not enough