But a higher borrowing cost is not a problem unless it is so prohibitively high that it prevents lending, which, judging by the relatively steady loan amounts, it has not.
The necessary supply of funds is there, it's just that no one trusts anyone, so they are charging lots more for the risk.
For an analogous situation, consider this: The Fed decides to institute a lottery, where they pick a random bank every day. Whichever bank is picked gets shut down, and all their creditors and depositors get nothing. This is obviously very bad for whichever bank is picked, and bad for anyone who lent money to that bank. No one knows who is going to be next, so they charge everyone higher rates to account for the risk. There is still plenty of money to lend, and there is still a market for the loans, it's just that there is extra risk of a random insolvency event.
In the real world, the illiquid and non-transparent Asset Backed Securities are like the Fed lottery, in that, by marking them to market, all it takes is one lowball transaction by third parties to crater a bank's balance sheet, forcing it into insolvency. Since no one knows who still is at risk, they are charging higher rates. It's not because they don't have the money to lend, it's because it is better to have the money sit idle than to lose it. (And in the case of some banks, it is better to have cash on hand in case their own asset-backed securities become worthless. Even lending it to a perfect borrower is riskier in that case, because even if the borrower can repay, it's no good to the bank if they need the cash in a pinch.)