VIO Mode...VIO is not supported by default.
SIG people have made a new shell with translation layer to let VIO use Korean characters, tho.
Using Korean is not the easiest part in eCS, but quite doable nowadays, thanks to those Korean SIG people..
As for user counts...I cannot be so sure...But we are not yet extinct..
But as the stats say, 96% of Korean desktop are MS OS, so I do not think the number to be too high..