$yoast_title = get_post_meta( $post->ID, '_yoast_wpseo_title', true );
if ( empty( $yoast_title ) ) {
    $wpseo_titles = get_option( 'wpseo_titles', [] );
    $yoast_title  = isset( $wpseo_titles[ 'title-' . $post->post_type ] ) ? $wpseo_titles[ 'title-' . $post->post_type ] : get_the_title();
}
echo wpseo_replace_vars( $yoast_title, $post );