What we should expect is for banks to protect themselves as businesses by changing compensation to account for long term risk. And if they fail to do that organically, we should acknowledge that the market is failing in a dangerous way and more regulation around compensation is needed.
If you don't let big banks fail, then nobody ever has to worry about counterparty risk, and they won't keep an eye on each other to see if one bank is taking too much risk or backing too many bets.
If I had some sort of magical power to enact this kind of reversal to where ibanks were once again partnerships, I'd do it in a heartbeat.
We quite correctly should expect governments to (have) ensured that these corporations could be allowed to collapse, indeed they (bravely) did with Lehman, just AIG was worse.
We also should expect that if you give someone 10-40 years salary each year, then that bonus really really should be well aligned with the stockholders own goals, or they will act in their own best interest (correctly).
The only thing that turned a disaster into a once in a century clusterfk was being unable to let them collapse.
So thats surely the public policy takeaway here.
If you're making $1M-$10M a year, the downside to a 5% or 10% chance of your employer going bankrupt is not so large that you're going to reduce your income to prevent that. And if you are, they'll just replace you with someone who is less "risk averse."