A few months back Gearbox contended that they had a "three gun" version of the Borderlands 3 box art, and thanks to San Diego Comic-Con, we have proof that it exists.
Captured by ResetEra user vestan, Gearbox evidently had a "Museum of Mayhem" exhibit of sorts for the series, which showcased unused box art concepts. Yes, the three gun idea was present (but with a foot instead of a third finger), as were a few others that you can view here compliments of vestan.
There's a few things to unpack here. The foot was completely unexpected and very true to the spirit of the series, to the point where I think it actually fits better than the already impressive final "zen" motif. The Miley Cyrus "Wrecking Ball" one is a few years too late, but I did the grittier black and white art (which reminds me of an H. R. Giger painting), and this one right here, which is classy as hell.
Either way, it's box art. I'm sure the creative teams and the marketing folks alike felt like the zen cover would get them the most eyes, and in the end, the quality of the actual game matters the most. I still wouldn't mind a few of these as alt-cover pack-ins though! As intimated recently, three gun might be on the docket already.
Borderlands 3 Scrapped Cover Art [ResetEra]