Sure. It's a bag, it's flexible. Just not infinitely so.Does it actually say that*? Could it also be 2x4x8 or 2x3x10.66 or whatever you need that interior space to be? It is magic. I always assumed it conformed to whatever it need to be.
The phrasing is ambiguous, but at least quote the whole thing.* It does not. The description describes the exterior only:
"...its outside dimensions, roughly 2 feet in diameter at the mouth and 4 feet deep."
"This bag has an interior space considerably larger than its outside dimensions, roughly 2 feet in diameter at the mouth and 4 feet deep."
And the picture of it, a satchel with a shoulder strap, is clearly not of a bag four feet long.
You could read it either way, but I don't think it's a coincidence that a symmetrical space four feet deep has a capacity of 64 cubic feet.