Well, I fail to see why you seem to care so much? I mean, maybe if you used a bit of talent (granted that you had some) and, trained it a bit, it would still be pretty strong.
I mean, I wouldn't throw a huge fit over it. Infact, had it happened to me, I wouldn't even be surprised due to the fact that it's a legendary. And, since it happens to be one, the odds of it being a 'good one' is pretty slim considering how the entire chance of being lucky in the game is very slim itself.
So, I don't know. I would just be pleased that I caught it. :/
By the way, you ask "Why would the game **** me over this much?". Well, I don't know, but, to me, it seems like the game makes a priority in doing this... Just for the sake of challenge maybe? I don't know. Or maybe they just like to toy with our emotions, because, they know it's easy to do.