Very subjective market

What rule, if entirely removed from the NFL rulebook, would change the sport the most? Note that the rule will not be altered or replaced, but simply deleted and disregarded. Scoring rules do not apply. Ideally, this rule still allows the sport to function (although very differently), so don’t choose any rule that leaves a notable gap in the gameplay (ex. removing kickoffs)

What single rule do you think holds together the fabric of the sport, and what would make it the most unrecognizable?

Definitely not my best work 😅

Thank you for participating!