Google did not make RCS; RCS is made by GSM consortium as succession of SMS, Google extended it to add some extra features such as end to end encryption (but only when messages are routed through their servers).
China mandated 5G sold in China must support RCS, hence why Apple added support for this. Since Google is basically banned in China, you can pretty much bet RCS going into/out of China is going to be unencrypted.
So you’re basically stuck between getting inferior unencrypted messages, or routing everything through Google.
Google did not make RCS; RCS is made by GSM consortium as succession of SMS, Google extended it to add some extra features such as end to end encryption (but only when messages are routed through their servers).
China mandated 5G sold in China must support RCS, hence why Apple added support for this. Since Google is basically banned in China, you can pretty much bet RCS going into/out of China is going to be unencrypted.
So you’re basically stuck between getting inferior unencrypted messages, or routing everything through Google.
Avoid RCS like the plague.