This was changed in rev 1.2 of link.2 in 1996.  I don't think we
want to make it sound like this behavior is OpenBSD-specific since
most systems disallow hard links to directories.

Perhaps something like this.

 - todd

Index: lib/libc/sys/link.2
===================================================================
RCS file: /cvs/src/lib/libc/sys/link.2,v
diff -u -p -u -r1.30 link.2
--- lib/libc/sys/link.2	25 Mar 2024 17:57:07 -0000	1.30
+++ lib/libc/sys/link.2	18 Jul 2024 02:25:00 -0000
@@ -65,15 +65,13 @@ is removed, the file
 .Fa name2
 is not deleted and the link count of the underlying object is decremented.
 .Pp
+For the hard link to succeed,
 .Fa name1
-must exist for the hard link to succeed and both
+must exist and not be a directory, and both
 .Fa name1
 and
 .Fa name2
 must be in the same file system.
-As mandated by POSIX.1
-.Fa name1
-may not be a directory.
 .Pp
 The
 .Fn linkat