Earlier quoted context omitted.
Someone once tried this on me during Friday drinks and I successfully conquered the challenge with "tar --help". The challenger tried in vain to claim that this was not valid, but everyone present agreed that an exit code of zero meant that it was a valid solution.
I seem to remember "tar xvf filename.tar" from the 1990s, I'll try that out. If I'm wrong, I'll be dead before I even notice anything. That's better than dying of cancer or Alzheimer's.
tar cvf - -C /foo/bar baz | zstd > foo.tar.zstd