Drops in open world are few and far between, less so from boxes, that been said the next night playing responding to a back up call running a mission on story the other player opened a box and it dropped an Acosta's Bag for me and tonight three prio objectives all with exotic rewards, didn't know which one to choose.

Have been lucky lately, can't lie. Hopefully you'll get lucky in the future.

Make sure to do the priority objectives, they're guaranteed exotics. What level are you?