What is this fascination with iso6400?

Adventsam wrote:

Do you think you will get quality images at iso6400 with any system, ever? they may be ok but useful for what exactly? Why is a forum dedicated to a lower-end of camera systems seemingly obsessed with iso6400? OK, maybe camera y isnt as good as x at iso6400, who gives a xxxx, buy some decent glass. You would have to be shooting in a tunnel at night not to be able to get a decent result with f1.4/1.8 glass at iso1600, even 3200 is the max you want to be at, shotts above these iso's are really because there is no alternative, we've run out of f stops, we are at long focal lengths, we cant use flash. But let's be honest most of us are shooting closer to base, aren't we?