SELECT 
  cscart_discussion.object_id AS product_id, 
  AVG(
    cscart_discussion_rating.rating_value
  ) AS average_rating, 
  cscart_discussion.type AS discussion_type, 
  cscart_discussion.thread_id AS discussion_thread_id 
FROM 
  cscart_discussion 
  LEFT JOIN cscart_discussion_posts ON cscart_discussion_posts.thread_id = cscart_discussion.thread_id 
  AND cscart_discussion_posts.status = "A" 
  LEFT JOIN cscart_discussion_rating ON cscart_discussion.thread_id = cscart_discussion_rating.thread_id 
  AND cscart_discussion_rating.post_id = cscart_discussion_posts.post_id 
  AND cscart_discussion_rating.rating_value != 0 
WHERE 
  cscart_discussion.object_id IN (
    24185, 24181, 24204, 24172, 24217, 24211, 
    24177, 24186, 24200, 24197, 24196, 
    24210, 24208, 24175, 24178, 22731, 
    23137, 23009, 22732, 22581, 23384, 
    23010, 23366, 22733
  ) 
  AND cscart_discussion.object_type = "P" 
  AND cscart_discussion.company_id = 1 
GROUP BY 
  cscart_discussion.object_id

Query time 0.00065

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_discussion",
          "access_type": "range",
          "possible_keys": ["object_id", "idx_company_id"],
          "key": "object_id",
          "key_length": "10",
          "used_key_parts": ["object_id", "object_type", "company_id"],
          "rows": 24,
          "filtered": 100,
          "index_condition": "cscart_discussion.company_id = 1 and cscart_discussion.object_id in (24185,24181,24204,24172,24217,24211,24177,24186,24200,24197,24196,24210,24208,24175,24178,22731,23137,23009,22732,22581,23384,23010,23366,22733) and cscart_discussion.object_type = 'P'"
        }
      },
      {
        "table": {
          "table_name": "cscart_discussion_posts",
          "access_type": "ref",
          "possible_keys": ["thread_id", "thread_id_2"],
          "key": "thread_id_2",
          "key_length": "6",
          "used_key_parts": ["thread_id", "status"],
          "ref": ["lillyshop_lillyshop.cscart_discussion.thread_id", "const"],
          "rows": 2,
          "filtered": 100,
          "attached_condition": "trigcond(cscart_discussion_posts.`status` = 'A')"
        }
      },
      {
        "table": {
          "table_name": "cscart_discussion_rating",
          "access_type": "eq_ref",
          "possible_keys": ["PRIMARY", "thread_id"],
          "key": "PRIMARY",
          "key_length": "3",
          "used_key_parts": ["post_id"],
          "ref": ["lillyshop_lillyshop.cscart_discussion_posts.post_id"],
          "rows": 1,
          "filtered": 100,
          "attached_condition": "trigcond(cscart_discussion_rating.thread_id = cscart_discussion.thread_id and cscart_discussion_rating.rating_value <> 0 and trigcond(cscart_discussion_posts.post_id is not null))"
        }
      }
    ]
  }
}

Result

product_id average_rating discussion_type discussion_thread_id
22581 D 23832
22731 D 23983
22732 D 23984
22733 D 23985
23009 D 24264
23010 D 24265
23137 D 24396
23366 D 24633
23384 D 24652
24172 D 25459
24175 D 25462
24177 D 25464
24178 D 25465
24181 D 25468
24185 D 25472
24186 D 25473
24196 D 25483
24197 D 25484
24200 D 25487
24204 D 25491
24208 D 25495
24210 D 25497
24211 D 25498
24217 D 25504