My point is, as you said there are different views on what Islam is, Sunni.. etc. And I assume that even within these different ones, not everyone would agree with what Taliban is doing, what ISIS is doing, so all these Muslims are "supporting" different views of what they believe is correct and there is all these teachers, including parents I assume could be called teachers to their children, teaching others how to be a "true" Muslim according to whatever they themselves believe. My point being, that the system or what to call it, might be pretty broken, especially if it is as you say, that the Quran state that you shouldn't teach others what it says as if we were experts, because it seems that everyone with such believe claim to be an expert. Like you follow Islam and have tagged yourself as a Twelve seeker, don't know if that is something special within Islam or not, but I assume you disagree with Taliban or ISIS in regards to their view on Islam, so for you to be able to do that, doesn't you have to "claim" to know more than their teachers do about Islam and thereby you yourself become sort of a self proclaimed expert, even if that is not your intention?
Don't know if what I say makes sense?