One asserts that nerds want to know the details for ego reasons.
The other asserts that he (presumbly as a self-proclaimed "nerd" in this situation) wants to know the details because otherwise he has no idea if the product is even useful.
If the product being sold is actually that simple e.g. "trade stocks with a few clicks" thats fine. But for anything that requires customisation, integration or any kind of technical support thats not true. You need to know the details to know if it will work.
This very much matches the stereotypical enterprise sales disaster i.e. buzzwords and flashy things sold to c-suite that are then suffered by those who actually use them and find that it doesn't do what they need
EDIT: also in this context where the article title specifically mentions "technical documentation" we are clearly not looking at the super simple type of product.