I was surprised that to learn that HKT weren't part of Scala from the beginning and had to look that up. You're a bit wrong about when that happened: it was Scala 2.5 in 2007, not 2.8 which was released in 2010.
I am a native Russian speaker and a former Korean language major. I would estimate that the modern Korean writing system has roughly the same amount of exceptions and non-phonetic spellings as the Russian one.
For example, the letter ㅎ (h) is not pronounced in a lot of cases. Some other consonants are reduced depending on their position in the syllable, etc.
The illusion that Korean is "pronounced as written" is created by the fact that Koreans are extremely happy when you learn to speak their language at all. I as a Russian speaker would also rather hear you pronounce Russian words as they are written than not try to learn Russian at all :) But as soon as you start working on sounding as close to native as possible, that illusion of simplicity quickly breaks down.