The line of logic is kind of lost on me. So, does IB offer Korean stocks? If not then you can't possibly compare the two. If IB offered Korean cash equity to institutionals but not retail then it would first beg the question why. It does not necessarily have to be due to regulatory hurdles.
It is true. We will shortly (hopefully < 1 month) be offering Taiwan stocks followed by Korea thereafter. A lot of effort has gone on behind the scenes on what should be a solid offering that will be competitive on all fronts. More to come after our launch.