True, but all you're setting up is multiple lines of dominoes flowing through and from the biggest banks. If one fails, because of being market neutral means you gamble on one failing, while countering with one doing well, constantly; then the contagion flows in far more directions and smaller banks can't deleverage that quickly. When they do, they fail more banks and those failures go to a bigger bank quicker.
We've seen how this played out before in 2008, and set up the exact same scenario, hoping banks have learned their lesson this time. 8 years is a long time to cook, and forger things, when you're risky, leveraged, self regulating, salary frozen bit still get bonuses on risky ventures, and profiting both ways. We'll see.