That's quite right. They always bring their own version of every tech and ban the westerner version. That's how China deals with the west but it is not like it won't have any impact on bitcoin. It will have its consequences. Millions of (some may even say billions) Chinese people will be forced to use the C-BTC and that's probably create a pressure on the btc prices. In the long term it will be fine... unless the west bans it too.
Let the bans begin, we shall see who wins in the end.
Tip: It won't be them. ₿ is not "foreign currency", its world currency. This is why these short sighted politicians can't get it, they think its just another $ or €, a digital variation, so they think all need is a digital ¥, as always, thinking they can outsmart the "westerners".
They so wrong, history will teach them (again) that rejecting wealth creation can only affect them negatively. But not until some decades and lots of bureaucratic debate within the party, perhaps when the old leaves and the young takes over...