"Go fast and break things" is a good thing if you're working on stuff nobody needs, or stuff that doesn't make a lot of money.

Breaking a social network that 2,000 people use and makes no revenue is fine as long as you learned something from it that makes it easier to get that 2,001st user or first dollar. Breaking a hospital's IT network could kill someone and should have consequences. Breaking amazon.com costs tens or hundreds of millions of dollars and should have consequences.

GFBT's usefulness, like most things, changes based on the scale at which you apply it. Calling it stupid is reductive at best.