Don't confuse the work that investment banks do with the work that NASDAQ does or with high-frequency trading.
In addition, the reason why GS has less traders and more developers is more to do with government regulations preventing GS from doing certain types of trading. Not because developers or AI is better. Dumb article.
Such as: "Buy these sub-prime assets that we've bundled into CDOs. By the way, we're actively betting against you and stand to make a ton of money when they tank."
Source: hedge fund trader who fights banks all the time, but doesn't agree with their scapegoating.
https://www.youtube.com/watch?v=ccjZEvBGOuk
And to be fair to GS (not that it is the widow and the orphan), the "shitty deal" wasn't a reference to the collateral of the CDO, but to the fact that they didn't manage to sell a position on that transaction.
And you will get better advice when that advice is data-driven. And you need the data because it's GS's proprietary data. If you're paying for a relationship, all you're really paying for is a smiling human face to read the numbers on the screen to you.