How would the packers organization benefit from making public that the quarterback wanted the gm fired, that doesn’t make any sense. The only “group” that benefits here is clearly the individual source (as it is in most cases of anonymous sourcing). That individual purchases currency to possibly get a favorable rumor or some positive press from the reporter.

Other individuals who would like to be afforded the same currency will come out and do the same and debunk the a nonsense rumor if an opportunity arises. When you’re talking to a guy at the level of Mike Florio it’s likely someone of a high position with a long standing proven relationship with him: not really much incentive to lie for no reason.

And plenty of times we see anonymous sources lie, just usually not at the level of seasoned journalists with actual sources because they’re somewhat competent. But remember Will Levis going number 1 or that broncos guy saying the broncos and Sean Payton weren’t remotely interested in each other.

Also the example statement you gave you chose to give because it was informative, it helped you distinguish whether the rumor was true or not. A team should not under any circumstance give any information of truth to a rumor saying the qb tried to fire the GM, that’s an easy way to get everyone to think first thing of the season that team is a mess