I can only say that it is already possible today to invest assets securely by holding cash, buying Danish government bonds or making deposits in commercial banks up to the guaranteed limit of approximately kr. 750,000. Full coverage of larger deposits can be obtained by spreading deposits on several banks so that the limit of kr. 750,000 is not exceeded in any one bank.
A third argument is to establish a back-up system that can take over if the current payments infrastructure is disrupted. Establishing a payment system that is completely independent of the existing system would require considerable resources. And a new system would still be subject to some of the same dependencies as the current system, such as the electricity grid.