Comment 1 for bug 1895302

I think this postinst bit never considered the fresh install case:

# special case of having /etc/default/motd-news removed by hand
# signal the motd-news-config package that this happened, so that
# it does not put back the file with default contents which would
# re-enable motd-news
motd_news_config="/etc/default/motd-news"
if [ ! -e ${motd_news_config} ]; then
  if [ ! -e ${motd_news_config}.dpkg-remove ]; then
    if [ ! -e ${motd_news_config}.dpkg-backup ]; then
      touch ${motd_news_config}.wasremoved
    fi
  fi
fi

Having it only act on upgrades might be the easier fix. I'll test.