How to correctly call the value of the product meta field in the cart?

Question

WordPress

I need to be able to substitute a different price for a certain amount of goods.
From 50 pieces so that the price is prescribed differently. I want to take the value of this new price from my added numeric meta field.

There is a snippet that does a very similar thing - changing the cost of a product from the required number of pieces, but with a percentage discount. Works great.

add_action( 'woocommerce_before_calculate_totals', 'phpsof_quantity_based_pricing', 9999 );
 
function phpsof_quantity_based_pricing( $cart ) {
 
    if ( is_admin() && ! defined( 'DOING_AJAX' ) ) return;
 
    if ( did_action( 'woocommerce_before_calculate_totals' ) >= 2 ) return;  
    
 
    // Define discount rules and thresholds
    $threshold1 = 50; // Change price if items > 50
    $discount1 = 0.05; // Reduce unit price by 5%
    $threshold2 = 100; // Change price if items > 100
    $discount2 = 0.1; // Reduce unit price by 10%
 
    foreach ( $cart->get_cart() as $cart_item_key => $cart_item ) {
      if ( $cart_item['quantity'] >= $threshold1 && $cart_item['quantity'] < $threshold2 ) {
         $price = round( $cart_item['data']->get_price() * ( 1 - $discount1), 2 );
         $cart_item['data']->set_price( $price );
      } elseif ( $cart_item['quantity'] >= $threshold2 ) {
         $price = round( $cart_item['data']->get_price() * ( 1 - $discount2 ), 2 );
         $cart_item['data']->set_price( $price );
      }    
    }    
 }

I wanted to try replacing round( $cart_item['data']->get_price() * ( 1 - $discount1), 2 ) with my meta field $cart_item['data']->get_meta( '_opt_price', true )
This is a meta field for the product, but in the cart you need to refer not to $product, but to $cart_item['data'], but that didn't work.
How to correctly access the product meta-field from the cart?

First of all, I thought that somehow I added the meta field incorrectly, but compared with the numeric pls existing in the admin panel, such as _stock, $cart_item['data']->get_meta( '_stock', true ) didn't work either.

How to correctly call the value of the meta field?

I am very happy for those who use crack plugins and don't sweat it, but I would really like to deal with the meta field.