Magento 2: Exclude group products in list page using a plugin

If you want to exclude group products in category page then follow below steps:

1. Put below code in your module di.xml file.

<type name="MagentoCatalogModelLayer">
 <plugin name="LayerPlugin" type="VendernameModulenamePluginLayer"/>
</type>

2. The next step is to create Layer.php file in your module and paste below code in VendernameModulenamePlugin folder

<?php
namespace VendernameModulenamePlugin;

use MagentoCatalogApiCategoryRepositoryInterface;
use MagentoFrameworkExceptionNoSuchEntityException;
use MagentoCatalogModelResourceModelProductAttributeCollectionFactory as AttributeCollectionFactory;

class Layer
{
 /**
 * Product collections array
 *
 * @var array
 */
 protected $_productCollections = [];

 /**
 * Key which can be used for load/save aggregation data
 *
 * @var string
 */
 protected $_stateKey = null;

 /**
 * Core registry
 *
 * @var MagentoFrameworkRegistry
 */
 protected $registry = null;

 /**
 * Store manager
 *
 * @var MagentoStoreModelStoreManagerInterface
 */
 protected $_storeManager;

 /**
 * Catalog product
 *
 * @var MagentoCatalogModelResourceModelProduct
 */
 protected $_catalogProduct;

 /**
 * Attribute collection factory
 *
 * @var AttributeCollectionFactory
 */
 protected $_attributeCollectionFactory;

 /**
 * Layer state factory
 *
 * @var MagentoCatalogModelLayerStateFactory
 */
 protected $_layerStateFactory;

 /**
 * @var MagentoCatalogModelLayerItemCollectionProviderInterface
 */
 protected $collectionProvider;

 /**
 * @var MagentoCatalogModelLayerCategoryStateKey
 */
 protected $stateKeyGenerator;

 /**
 * @var MagentoCatalogModelLayerCategoryCollectionFilter
 */
 protected $collectionFilter;

 /**
 * @var CategoryRepositoryInterface
 */
 protected $categoryRepository;

 /**
 * @param LayerContextInterface $context
 * @param LayerStateFactory $layerStateFactory
 * @param AttributeCollectionFactory $attributeCollectionFactory
 * @param MagentoCatalogModelResourceModelProduct $catalogProduct
 * @param MagentoStoreModelStoreManagerInterface $storeManager
 * @param MagentoFrameworkRegistry $registry
 * @param CategoryRepositoryInterface $categoryRepository
 * @param array $data
 */
 public function __construct(
 MagentoCatalogModelLayerStateFactory $layerStateFactory,
 AttributeCollectionFactory $attributeCollectionFactory,
 MagentoCatalogModelResourceModelProduct $catalogProduct,
 MagentoStoreModelStoreManagerInterface $storeManager,
 MagentoFrameworkRegistry $registry,
 CategoryRepositoryInterface $categoryRepository,
 array $data = []
 ) {
 $this->_layerStateFactory = $layerStateFactory;
 $this->_attributeCollectionFactory = $attributeCollectionFactory;
 $this->_catalogProduct = $catalogProduct;
 $this->_storeManager = $storeManager;
 $this->registry = $registry;
 $this->categoryRepository = $categoryRepository; 

 }

 public function afterGetProductCollection(MagentoCatalogModelLayer $subject, $collection)
 {
 $collection->addAttributeToFilter('type_id', array('eq' => 'grouped'));
 return $collection;
 }
 
}