> How do you quantify the cost of missing out on good people that you just assumed didn’t fit the mold? How expensive is that?

That is a cost that isn't easily quantifiable. However, the cost of wrong hires is easily quantifiable based on the time effort required to (attempt) to get a new hire going.

Considering that most companies are looking to minimize risk and the potential benefit is not quantifiable I would estimate the chances to skip the interviewing process as minimal.