我可以看出你想说得很清楚，但这仍然是一个令人困惑的问题，让我的大脑有点崩溃。我想这可能会达到你想要的，但我不能完全确定我是否正确理解你。无论如何，请尝试一下，它可能会起作用，也可能不会起作用：

$downloads_parent_posts = get_posts( array(
    \'post_type\'        => \'downloads\',
    \'orderby\'          => \'title\',
    \'order\'            => \'ASC\',
    \'tax_query\' => array(
      \'relation\' => \'AND\',
      array(
        \'taxonomy\'         => \'download-category\',
        \'terms\'            => $term->term_id,
        \'field\'            => \'term_id\',
        \'include_children\' => false
      ),
      array(
        \'taxonomy\'         => \'download-category\',
        \'terms\'            => get_term_children($term->term_id, $term->taxonomy),
        \'field\'            => \'term_id\',
        \'operator\'         => \'NOT IN\',
      )
    ),
) );