Adding Twitter Usernames

See the “How do I add my Twitter account?” section of the FAQ:
https://www.ads-software.com/plugins/twitter-cards/faq/

The code below only pick specified twitter, how about for those users that have included their twitter account on their profile.

Does it automatically add their twitter account?

function twitter_custom( $twitter_card ) {
    if ( is_array( $twitter_card ) ) {
        $twitter_card['creator'] = '@niall';
        $twitter_card['creator:id'] = '1085';
    }
    return $twitter_card;
}