The NFL has routinely made rule alterations over the past decades, many of them leading to their current success. If they can implement others that increase player safety as well, why not do it?
That's a fine concept, but this is a terrible rule.
It's potentially awarding a precious extra possession to a team for being good at one thing (passing offense) or potentially taking a precious possession away from another team for being poor at one thing (passing defense).
It's alarming to me that they are even toying with this idea. It sounds like something kindergartners came up with out on the playground.