Most probably this has nothing to do with 0.23, but with the underlying major Android version.
Encryption is mandatory by default since Android 10, so what you describe would match what an upgrade from an older major Android version to Android 10 does. (Also observed here for example … Samsung S9 encrypted after OTA update)
At which point are you prompted for the password?
Is it by chance the TWRP recovery prompting for the password? Or is it /e/OS prompting for it after booting?