Convert multidimensional json to array in js

Question

I am trying to select each member by converting a multidimensional json stored in longtext format in mysql to an array in js, but it fails.

Here's what I've tried:

Get data from mysql and convert it to json format. from php

if( isset( $_GET ) ){
    $id = $_GET['id'];
    $conn = db_connect();
    $id = mysql_fix_string( $conn, $id );
    
    $result = $conn->query("select _usage from SVM where id='$id'")or die(mysqli_error( $conn ));
     
    $rows = array();
    while( $re = mysqli_fetch_assoc( $result ) ){
       $re['_usage'] = n12br( $re['_usage']);
       $re['_usage'] = html_entity_decode( $re['_usage']);
       $re['_usage'] = stripslashes( $re['_usage'] );
       $rows[] = $re;
    }
    print( json_decode( $rows ));
}   

js

$(document).on('click', '.view-subtitle', function(e, ele){
       const id = (this).attr("data-value");
       $.ajax({ url:'connect_data.php',
            type:'GET',
            data:{id: id},
            success: function(html){
               const result = JSON.parse(html);
               console.log( typeof( result ) );
               console.log( result[0] );
               console.log( result[0].subtitle );
               console.log( typeof( result[0].subtitle ));
           },
           error: function(e){
              alert(e.responseText);
           } ,
           return false;
    });