The new RELRO option is described as "enable -z relro in ELF linker by default".
This is not useful to the reader. The name of the option implies that it enables that feature. What the user installing a port needs to know is what effect that option will have.
For example: "Enable Relocation Read-Only memory corruption mitigation by default."
I think it's important that the option description *also* include the string relro. A user interested in mitigations will immediately know what a relro option does, while the more verbose description takes more thought/consideration.
E.g. something like
Enable relocation memory corruption mitigation (-z relro) by default.