Template: Blocks shouldn't be draggable if template is locked

[Soean]

Describe the bug
I created a template for an custom post type. If I add 'template_lock' => 'all' I still see the grab cursor and can drag the block. I am not able to drop and change the position. But i shouldn't be able to start to drag.

To Reproduce
Example Template:

function myplugin_register_book_post_type() {
    $args = array(
        'public' => true,
        'label'  => 'Books',
        'show_in_rest' => true,
        'template_lock' => 'all',
        'template' => array(
            array( 'core/image', array( 'layout' => 'column-1' ) ),
            array( 'core/paragraph'),
        ),
    );
    register_post_type( 'book', $args );
}
add_action( 'init', 'myplugin_register_book_post_type' );

Screenshots