Basel 2 eliminated reserves.
The amount of credit in the system is limited by 1/Reserve so 1/0 = infinity. i.e. There's no limit on credit creation! Credit is now very fungible with money so there's effectively no limit to the money supply i.e. the state has abandoned it's role as regulator of the currecny.
No reserves means that the currency has no owner. The credit market becomes a commons and you'd best have as much as possible ASAP before someone else takes it.
This incentivised banks to lend the most rather than lend to the best.
and now the commons has inevitably "run out".
If governments are going to keep their currency monopoly then reserves are going to have to be based on the affordability of the assets purchased, especially mortgages. It's no point saying 3% of mortgages have to be held in reserve (30 times lending) to stop these problems happening in the future we need to demand that regulators specify that 3% mortgage reserves are ok when houses are 4 times earnings after tax.
BTW. Here's the tragedy of the commons game