... But the explanation on how openings prevent those blunders ...
Can you identify a specific sentence where it was stated that openings prevent those blunders?
"... you've limitations for this game, and that has nothing to do with openings nor books. It's you. See, opening a line for an attack against the own King while leaving something defenseless makes most of us alert, but for you it's something that just happens. ..." - JMurakami
... In such books you get a few typical tactical shots and then the middlegame reaches something unrecognizable. Opening books are useless for that. ...
Is something only worthwhile if it is useful for everything?