Again, you can get all of that without needing a CBDC, just have the central bank build and run a regular payment system. It gets substantially more complex once you make it a CBDC, making the chance of success even smaller. For what gain? You actually introduce some tangible risks for the financial system, the fact that it's regulated doesn't eliminate that. See eg [0]: "Threats to financial intermediation in steady state arise mainly in situations where the central bank balance sheet expands, and triggers adjustment mechanisms that lead to more costly or less stable funding of the banking system, while in crisis times run risk may increase." The typical way to address those risks are holding limits, which add operational complexity (you need an overflow logic, you need a draft logic if you want to enable payments greater than the holding limit), and put some limits on programmability [1].
[0] https://www.imf.org/en/Publications/WP/Issues/2024/10/11/Cen...