Why doesn’t foreach( $wp_styles->queue as $handle ) print the handle of enqueued style from a plugin?

The following block of code returns a list of enqueued & registered styles.

function mg_print_styles() {
     
        global $wp_styles;
        foreach( $wp_styles->queue as $handle ) :
           echo '<div>Style <br />';
           echo "Handle: " . $handle . '<br />';
           echo "URL: " . $wp_styles->registered[$handle]->src;
           echo '</div>';
        endforeach;
}
add_action( 'wp_print_scripts', 'mg_print_styles', 101 );

It does not however display the handle of a style enqueued/registered by a plugin e.g. abc. Using, wp_style_is returns true.

$style = 'abc';
echo wp_style_is ( $style );

Additionally, it also returns an echoed value. enqueued, queue and registered all result in an output.

if ( wp_style_is ( $style , 'enqueued') ) {
    echo $style . " " . $list;
}