I’m not sure, but I would surmise that it wasn’t the box that killed those that touched it, but it was God that dwelled on the box that did the killing. (Sort of like Moses having to hide his eyes so he wouldn’t see God or he would die.)
If it is still around - it’s just a box now. (Okay - a REALLY cool box with hopefully some neat stuff still inside!)
God appeared to Moses as a burning bush that was not consumed. Told Moses that he could not see God in his real form.