magento2- custom categorycontroller not overriding

Question

Unable to override Magento\Catalog\Block\Product\ListProduct

etc\frontend\di.xml

<?xml version="1.0"?>
 <config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <preference for="Magento\Catalog\Block\Product\ListProduct" type="Vendor\Module\Block\Catalog\Product\ListProduct" />
 </config>

\Vendor\Module\Block\Catalog\Product\ListProduct.php

namespace Vendor\Module\Block\Catalog\Product;

use Magento\Catalog\Api\CategoryRepositoryInterface;
use Magento\Catalog\Model\Category;
use Magento\Catalog\Model\Product;
use Magento\Eav\Model\Entity\Collection\AbstractCollection;
use Magento\Framework\Exception\NoSuchEntityException;
use Magento\Framework\DataObject\IdentityInterface;
class ListProduct extends \Magento\Catalog\Block\Product\ListProduct
{
   public function __construct(
    /*passing all Constructors parameters to the parent class */
    \Magento\Catalog\Block\Product\Context $context,
    \Magento\Framework\Data\Helper\PostHelper $postDataHelper,
    \Magento\Catalog\Model\Layer\Resolver $layerResolver,
     CategoryRepositoryInterface $categoryRepository,
    \Magento\Framework\Url\Helper\Data $urlHelper,
    /*passing all Constructors parameters to the parent class */

    \Vendor\Module\Helper\Data $tglssearchHelper,
    \Magento\Catalog\Model\ResourceModel\Product\CollectionFactory $catalogResourceModelProductCollectionFactory,
    \Magento\Catalog\Model\Config $catalogConfig,
    \Magento\Store\Model\StoreManagerInterface $storeManager,
    array $data = []
) {
    $this->tglssearchHelper = $tglssearchHelper;
    $this->catalogResourceModelProductCollectionFactory = $catalogResourceModelProductCollectionFactory;
    $this->catalogConfig = $catalogConfig;
    $this->storeManager = $storeManager;

      parent::__construct(
        $context,
        $postDataHelper,
        $layerResolver,
        $categoryRepository,
        $urlHelper,
        $data
    );
    //$this->tglssearchHelper = $tglssearchHelper;
}

 protected function _getProductCollection()
{
    echo 'getproducolle';
    ....
}
}

Magento core _getProductCollection() is executing. I have cleared var/generation.

My di.xml is under /etc/frontend