>Nobody is "blaming the victims". They are founders,
Founders can't be victims? I'll remember that if I ever feel the need to mug somebody.
>should know at least basic rules of what they are doing
There are no static "basic rules". What you "should know" is constantly changing. The more of this kind of junk you force would-be founders to know the more people are taking out of the pool of potential founders based on things that probably aren't relevant to what their startup would have been about.
>If you want successful business it is not enough to be "good at creating products" and completely ignorant on basic business issues.
This isn't being completely ignorant of basic business issues, this is being ignorant of the current traps that people who are supposed to be enablers will set for you.
>If I rephrase this instead ... would you still disagree.
Possibly. First of all, this isn't the case of "do simple maths", it's the case of learning ins and outs of something not related to your passion, namely how all kinds of stock types behave in various potential scenarios. And further, I don't want to exclude the wacky genius who understands something (say, search) vastly better than anyone else but just doesn't care about learning things like this.
>And it is good that unsuccessful business fails.
On its own merits, yes. Businesses failing based on things that have nothing to do with the actual business is not good. It's inefficient and may send the wrong signal to others, namely that X isn't a valid market when the reason for the failure actually had nothing to do with that.