Why is __PAGEZERO missing from vmmap output at Darwin 21.2.0

when I run vmmap for a process the regions start with the __TEXT entry rather than __PAGEZERO as in [sample output at documentation]( https://developer.apple.com/library/archive/documentation/Performance/Conceptual/ManagingMemory/Articles/VMPages.html) otool -l also shows

Load command 0
      cmd LC_SEGMENT_64
  cmdsize 72
  segname __PAGEZERO
   vmaddr 0x0000000000000000
   vmsize 0x0000000100000000
  fileoff 0
 filesize 0
  maxprot 0x00000000
 initprot 0x00000000
   nsects 0
    flags 0x0

uname -mrsvp output is:

Darwin 21.2.0 Darwin Kernel Version 21.2.0: Sun Nov 28 20:28:54 PST 2021; root:xnu-8019.61.5~1/RELEASE_X86_64 x86_64 i386

Why is it so?