add_filter( 'author_rewrite_rules', '__return_empty_array' );

上記で下記のようなリライトルールのすべてが削除される。

[ "author/([^/]+)/feed/(feed|rdf|rss|rss2|atom)/?$" ] => "index.php?author_name=$matches[1]&feed=$matches[2]"
[ "author/([^/]+)/(feed|rdf|rss|rss2|atom)/?$" ] => "index.php?author_name=$matches[1]&feed=$matches[2]"
[ "author/([^/]+)/embed/?$" ] => "index.php?author_name=$matches[1]&embed=true"
[ "author/([^/]+)/page/?([0-9]{1,})/?$" ] => "index.php?author_name=$matches[1]&paged=$matches[2]"
[ "author/([^/]+)/?$" ] => "index.php?author_name=$matches[1]"