How to update product salable quantity in Magento 2.4 programmatically?

I am trying to import products programmatically into a Magento 2.4.4 installation but I have problem setting the Salable Quantity. I cannot find a viable solution to this issue, please help if you can.

Here is the code I am using to set product Quantity (simplified):

use MagentoCatalogApiProductRepositoryInterface;
use MagentoInventoryApiApiDataSourceItemInterfaceFactory;
use MagentoInventoryApiApiSourceItemsSaveInterface;

public function __construct(
  ProductRepositoryInterface $productRepository,
  SourceItemInterfaceFactory $sourceItemFactory,
  SourceItemsSaveInterface   $sourceItemsSave
)
{
  $this->productRepository = $productRepository;
  $this->sourceItemFactory = $sourceItemFactory;
  $this->sourceItemsSave = $sourceItemsSave;
}

private function updateStock($product_id, $qty)
{
  $product = $this->productRepository->getById($product_id);

  $sourceItem = $this->sourceItemFactory->create();
  $sourceItem->setSourceCode('default');
  $sourceItem->setSku($product->getSku());
  $sourceItem->setQuantity($qty);
  $sourceItem->setStatus($qty > 0);
  $this->sourceItemsSave->execute([$sourceItem]);
}

After finishing import, I run manually reindex and cache flush:

bin/magento indexer:reindex & bin/magento cache:flush

When displaying the product grid, the product’s Quantity is set correctly but the Salable Quantity is always zero (0). Only after I edit/save the product in admin panel manually, the Salable Quantity is set correctly and equal to Quantity. But this is not a viable solution when having to import thousands of products.

Could you provide an example on how to set the Salable Quantity programmatically?

Thanks