Payment instruments that are safe, reliable, inexpensive, and available to all are essential to support economic activities. I think most people would agree that the central bank should continue to be responsible for supplying these instruments in the digital age as well. The rationale for issuing CBDC may basically rest on this.
CBDC functions not only as a means of payment but also as a store of value. In normal times, people may not be aware of the difference between central bank money and private 2  Walter Engert, Ben S. C. Fung, and Scott Hendry, "Is a Cashless Society Problematic?," Bank of Canada Staff Discussion Paper 2018-12, October 2018.