From what I have gathered the recommendation to choose boring tech usually has this idea factored in already and is more of a conclusion than an aspiration.

What one engineer can operate confidently doesn't necessarily extend to the rest of the team, who will have to support that system if that engineer leaves or has to work on other projects.

The lowest common denominator on a team is boring.

I think, the filter function should be something like operational-confidence * value-delivered.

High risk, high reward, etc.

This is an accurate summary of the article, down to where the author says he wish he'd said something other than "boring."