default or selected kernelversion does not have config value CONFIG_INET_PSP.
Result is shown for kernelversion 6.18-rc3

PSP Security Protocol support

modulename: psp.ko

configname: CONFIG_INET_PSP

Linux Kernel Configuration
└─>Networking support
└─>Networking options
└─>PSP Security Protocol support
Enable kernel support for the PSP Security Protocol (PSP).
For more information see:
https://raw.githubusercontent.com/google/psp/main/doc/PSP_Arch_Spec.pdf

If unsure, say N.

source code: