Cannot Replace the System GenericFolderIcon.icns File

In order to replace the standard blue folder icons in Finder I have my customized GenericFolderIcon.icns file. It used to be possible to temporarily remove SIP and replace the stock GenericFolderIcon.icns file with your own customized version in the folder /System/Library/CoreServices/CoreTypes.bundle/Contents/Resources/. I am no longer able to do that in Ventura as the system keeps telling me I do not have the permissions in that folder even after disabling SIP. I also tried booting in Recovery Mode from an external USB drive and doing the change using Terminal, but got a message that the file system is read only.

I will appreciate any advice as to how to gain access and replace the standard icon file.