Alternative music keeps staff alive

[Jean Abou Samra]

\version "2.23.12"

\layout {
  \context {
    \Score
    \remove Volta_engraver
    \remove Staff_collecting_engraver
  }
  \context {
    \Staff
    \consists Volta_engraver
    \consists Staff_collecting_engraver
  }
}

{
  \repeat volta 2 {
    c'1
    <<
      \alternative {
        \volta 1 c'1
      }
      \new Staff {
        \alternative {
          \volta 2 c'1
        }
      }
    >>
  }
  c'1
}




The example above shows that \alternative sometimes keeps staves
alive longer than they should be. I understand that this can look
like a contrived use case; if you want the context, look at the
first image on
https://lists.gnu.org/archive/html/lilypond-user-fr/2022-07/msg00060.html

Should I create this as a Defect ticket, or should I not have
recommended this syntax in the first place?

Thanks,
Jean