Central bank reserves aren’t the only assets that exist. Most countries already didn’t have a reserve requirement. CBRs are mostly required just for liquidity for interbank payments.
Banks that don’t have assets to cover all their liabilities (deposits) are insolvent. Non-delinquent loans are assets to the bank (liabilities to the customers) that are created when banks lend and create money (which become deposits - which are liabilities to the bank and assets to customers).
Only the central bank can originate money without creating debt.
Even the central bank can't originate money without creating debt. That's what money is, an exchangeable claim to resources, or assets. With base money, and the physical currency people hold in their wallet, the claim is notionally against the central bank's assets, that "back" the money and underly its value.
