Hi,

lchmod (= the effect of fchmod with flag AT_SYMLINK_NOFOLLOW)
is implemented since glibc 2.32, see
https://sourceware.org/bugzilla/show_bug.cgi?id=14578
https://sourceware.org/git/?p=glibc.git;a=commitdiff;h=752dd17443e55a4535cb9e6baa4e550ede383540

Here is a patch to update the man pages accordingly.