If the difficulty or labor of the bounty judge if the gun should be OP then why is my Bad Juju not OP like the Thorn? Tolands Legacy is far more tedious to complete then the Thorn bounty.

Tedious, not difficult. Given enough time, you can do it easily. The Thorn bounty is much more difficult to finish off. That last step is very difficult, especially if you're on your own.

A nightfall and 25 additional strikes along with the 10,000 crucible score compared to killing hive and 500 points in the crucible and then killing some PvE boss. Honestly those seem a bit even to me by difficulty. Void damage is not hard because you should be making progress every game unless you absolutely suck at crucible in which case you don't need the Thorn because then you really are a scrub. To me their difficulty is even but Tolands legacy is far more tedious which again brings my to question why the Thorn is so OP compared to the Bad Juju

It's not even a nightfall...you can do a weekly challenge at the lowest setting. It's not some PVE boss, it's surviving until Xyor, then managing to kill her, and that's not simple. Bad Juju is actually very useable in crucible, especially with a fast, accurate full auto perk. Thorn's made out to be this fantastical weapon that melts faces left and right. It's not that fantastic. It's a handcannon. Most handcannons kill rather quickly, wouldn't you say? I think the Last Word beats out Thorn when it's used in the right situations. And other handcannons and pulse rifles and auto rifles and fusion rifles and shotguns and sniper rifles and scout rifles beat out the Thorn. It's a gun.