It's not 50k+/hr, that's an inflated number based on you taking multiple ingame day cycles worth of a full clear of necklaces/rings(assuming you get the entire haul and nobody competed with you for even part of it on any of those days), stacking appraise gear, and hauling it all to a vendor in another domain that pays premium price.
I'm not saying this isn't a very easy way to make money - it is. I'm just saying it seems like you're purposefully fudging the numbers to make it seem like it's worse than it is. I'd bet real life money that if you set up a live stream, there is no possible way (short of somehow guaranteeing that nobody will go into the area long enough for it to reset repeatedly) you could make 50k+ in a single hour even once, let along consistently every hour with this method. Especially considering that ingame day cycles are (6x24) 144 minutes long and it takes more than one to rack up enough to be worth selling. That's like saying I made 1 million in gold in a single 10 minute harvest run, because I happened to get a white scarab that sold at auction for that much. It doesn't incorporate all the down time between runs or the times someone else beats you out for it.
Also, I don't even have a character currently that does this so it's not my defending my gold-getting methods (It's been about 2 years since I've done this, I just roll through and mess with other players I see doing it from time to time). I actually prefer ninja-looting, I enjoy the possibility of scoring a rare item and the challenge that comes with different dungeons. I found the pickpocket skill largely unrewarding and entirely useless outside of this one scenario. It's not too good; it's actually the hardest skill to pass all related checks and get away with an item undetected. Feel free to take a look at Pick Pocket on the NWN Wiki and the involved skill checks, it's STACKED in favor of the spotter (you need to pass a DC 30 check to even get an item at all, which is separate and often lower than the check to do it undetected. And you'll likely be doing it from stealth, so add hide/ms rolls in there too at the likely -10 penalty you'll get from grabbing the item). If you remove this, then this will just be another one of those skills that only gets used once in a blue moon in a DM event. I've pickpocketed players before and got more hate for that than I ever did for killing anyone, it's just not worth it . These NPCs are the only justification for taking the skill at all.
The only adjustment I'd like to see made here is an OCR bump on a failed pickpocket attempt. Somewhere along the lines of (minimum) what you get for casting magic in front of NPCs. If anything else, perhaps reduce the number of noblewomen in the district by 1/3 or half. But the problem here isn't really the pick-pocketing, it's lack of consequence for failure. If the guards came running on a failed attempt, this would stop being a low level (borderline npc ignoring if you ask me) jump-start. You'd actually have to incorporate stealth and a decent pickpocket score into this.
I personally say let rogues/bards have their thing (especially considering the stealth gear for these classes often sells for some of the highest prices on the server due to how rare it is, and how incredibly difficult it is to sneak without it). The only other two classes that get this skill are PrCs. It's not like every PC on the server is doing this, and it's not like the ones that are doing it are out there flooding the market with gold for everyone (I play a merchant after all, and there's still PLENTY of people who can't afford items priced 5k and below).