It's a fumble out of the end zone.
Another way to look at it is a fumble not recovered by the defense does not reward nor penalize the offense anywhere else on the field so why does it here?
Point well-taken, but there's an answer to that of course... the end zone is
the unique place "anywhere else on the field." It's inherently the end of the line, like nowhere else on the field. Once you cross the ball crosses that threshold, everything changes.
The fumble
has to reward someone, either the offense or the defense.
One may reply, "Well yes, but if a fumble goes into the end zone under the Holy Roller (Dave Casper) rule, and someone on offense other than the fumbler recovers in the end zone, then the ball goes back to where it was fumbled... which is exactly what we're pleading for here."
But wait. Notice "someone
on offense...
recovers in the end zone." That still is a difference... if someone on
defense recovers, then it self-evidently is a touch back.
This, again, is self-evidently a situation where there is no third option.
Could you choose to treat it like a Holy Roller play without catastrophically affecting the game, yes. You could. I won't lose sleep.
But the Holy Roller play doesn't involve an out-of-bounds situation. And the ordinary fumble out-of-bounds situation doesn't involve the end zone. When you have both elements, and you add to that the proposition that most often the defense
causes that fumble... it doesn't just drop out of Dave Casper's hands on its own... advantage, defense, imo... and there's just no compelling reason to change history on this one.
Footnote: Yes, I'm the same guy proposing an overhaul to the NFL's set-up, including conference structure and schedule format. (See NFL Zone "re-envisioned" thread.)
Because? Because there are benefits to be had. And so, it's not like I'm anti-change, obviously.