If I accept what you've written at face value (which I do), then it also strikes me that Seoul is one city where the emergence of Uber would have little impact on the taxi industry. But if Uber actually does have a significant impact, then it seems that the people want something that they are not currently being offered. Seems like a good experiment, not something that should be shut down.
You do have a point. I'd add that the historic pattern in Korea is to be allergic to foreign companies doing business there. Things like trade protectionism is a very political strong thing there because it keeps money inside the country. Sending <whatever percentage of a ride goes to Uber> outside of the country, when the alternative is to just update the very well done and current taxi system is a political non-starter.
I'd be highly surprised if they were ever allowed to operate. If Uber was allowed to go, I'd imagine some kind of tight regulation or high taxes on Uber service to make it less competitive than the normal service.
