Lateral Derived optimization is not applied when it should

create table user (

  user_id int primary key,

  user_name varchar(32)

);

insert into user select 

seq, concat('user-', seq) from seq_1_to_10000;

create table shipping_address(

  user_id int primary key,

  address text

);

insert into shipping_address select 

seq, concat('Address ', seq) from seq_1_to_10000;

create view user_info as

select U.user_id, user_name, address

from 

  user U

  left join shipping_address ADDR on U.user_id=ADDR.user_id;

create table orders(

  order_id int primary key,

  user_id int,

  amount double,

  key(user_id)

);

insert into orders select 

  seq, seq/100, 123 from seq_1_to_20000;

create view user_info2 as 

select U.user_id, user_name, ORD_TOTAL

from

  user U

  left join (select

               user_id, sum(amount) as ORD_TOTAL

             from orders

             group by user_id

            ) ORD_TOTALS

     on ORD_TOTALS.user_id=U.user_id;

MariaDB [test]> explain select user_name, ORD_TOTAL from user_info2 where user_id in (1,2);

+------+-----------------+------------+-------+---------------+---------+---------+----------------+------+-------------+

| id   | select_type     | table      | type  | possible_keys | key     | key_len | ref            | rows | Extra       |

+------+-----------------+------------+-------+---------------+---------+---------+----------------+------+-------------+

|    1 | PRIMARY         | u          | range | PRIMARY       | PRIMARY | 4       | NULL           | 2    | Using where |

|    1 | PRIMARY         | <derived3> | ref   | key0          | key0    | 5       | test.u.user_id | 4    |             |

|    3 | LATERAL DERIVED | orders     | ref   | user_id       | user_id | 5       | test.u.user_id | 49   |             |

+------+-----------------+------------+-------+---------------+---------+---------+----------------+------+-------------+

MariaDB [test]> explain select user_name, ORD_TOTAL from user_info2 where user_id=1;

+------+-------------+------------+-------+---------------+---------+---------+-------+-------+-------------+

| id   | select_type | table      | type  | possible_keys | key     | key_len | ref   | rows  | Extra       |

+------+-------------+------------+-------+---------------+---------+---------+-------+-------+-------------+

|    1 | PRIMARY     | u          | const | PRIMARY       | PRIMARY | 4       | const | 1     |             |

|    1 | PRIMARY     | <derived3> | ALL   | NULL          | NULL    | NULL    | NULL  | 19982 | Using where |

|    3 | DERIVED     | orders     | index | NULL          | user_id | 5       | NULL  | 19982 |             |

+------+-------------+------------+-------+---------------+---------+---------+-------+-------+-------------+

3 rows in set (0.001 sec)