For some reason when I read "Khan Academy" somewhere I instantly associate it with Star Trek and I can't take it seriously.
Honestly, how are you going to live life if any reminder of pop culture can distract you from a serious subject? And how are you going to interact with people if noticing such a thing (even if it's tremendously obvious) makes you feel the need to shout about it? Best to knock it on the head now.
Of course I don't really believe parent poster has that problem: it was making a little fun as mild chastisement for the terrible comment. I honestly think you could have interpreted it correctly if you hadn't been so quick to take offence.
This naturally seems to stem from their conscious efforts to promote a 'serious'/on-topic culture and humor's nature as being subjective and often hard to detect.