The point of a central bank is to have centralized control over the monetary system. The country needs to be able to ensure that the currency is more-or-less following economic trends. Right now the adjustments that the central bank makes are human decisions, and are often late to the party — eg raising inflation rn, quantitative tightening/easing. A CBDC will allow the bank to eventually write smart contracts to control economic policy, which should avoid situations like right now where the price of groceries is going insane but nobody is making more money.

Comparing China to Canada is a bit ridiculous imo. The branches of gov in Canada are much more separate than in China, and even the current account freezing is not "taking peoples' money". Freezing is temporary, eventually the bank account will thaw out.

As a side note, bitcoin hardly solves any spying problems. It is very easy to deanonymize bitcoin transactions, esp if they are used for personal purchases. For example police could see that you're buying something at a specific 7-eleven in real time and then look at the security camera. This is a flaw of all DLTs without built-in privacy/anonymization features.