NFL

I assume part of it being the design of the play is more of a jump play into a mass rather than a route and a defined coverage. And the fact that in theory it could usually be ruled uncatchable by most involved players, and also it may have something to do with the defenders all generally facing back towards the qb as well so they’re “making a play on the ball” which gives the defensive back the same rights as receivers to the path to the ball. While they could usually call playing through the back of the player, I think that can be negated by facing back often. You only get a clear path if they’re playing you not the ball. If they’re after the ball and knock you out of the way that’s a good play.