The LSB is a specification, and as such, should be provider neutral. But it contains many “hard‑coded” reference to GNU at many places. Ex. the ELF Linux's specific entries PT_GNU_STACK, PT_GNU_RELRO ...
I've been thinking about discontinuing the use of GNU Coreutils on my Linux systems, but to be honest, unlike many other GNU components, I can't think of any alternatives (on Linux). What alternatives ...