It is not a "Liquidity Problem": it is more correctly, a Debt Problem.
When banks (credit money creation) and central banks manufacture synthetic money, (QE), out of step with logical fiat monetary system basis (Money Increase must equate to "real" GDP increase), equals problem from disequilibrium.
The compliance issues and banker's concerns, relate to their excessive use (Abuse!) of Fractional Reserve Banking.
Nothing new here: indeed, in times gone by, bank crashes were quite common: mainly caused by bankers issuing valueless paper against deposits of real money.
Only major difference then was money in circulation enjoyed true intrinsic value, since it was tied, inexorably, to gold and silver.
Today, "money" is tied to a series of empty, valueless, promises
May 4th be with you