It would still be an issue with shared neutrals and individual RCBOsAnd 9 times out of 10 you can't split the lighting circuits due to a shared neutral on the landing light.
The dual rcd boards only comply on a new install where they are loaded correctly.
I totally agree that they should have been phased out by Amd2. Maybe we should all wait for the consultation on Amd3 and push for it ??