Filtered shows 0 with derived tables/views when optimizer_use_condition_selectivity is set to 3

CREATE TABLE t1 (a int) ;

INSERT INTO t1 VALUES (1), (1);

CREATE TABLE t2 (b int) ;

INSERT INTO t2 VALUES (9), (NULL), (7);

set @@use_stat_tables= PREFERABLY

set @@optimizer_use_condition_selectivity=3;

analyze format=json

SELECT * FROM (SELECT * FROM t1,t2) t WHERE b IS NULL;

ANALYZE

{

  "query_block": {

    "select_id": 1,

    "r_loops": 1,

    "r_total_time_ms": 0.4197,

    "table": {

      "table_name": "t2",

      "access_type": "ALL",

      "r_loops": 1,

      "rows": 3,

      "r_rows": 3,

      "r_total_time_ms": 0.0274,

      "filtered": 0,

      "r_filtered": 33.333,

      "attached_condition": "t2.b is null"

    },

    "block-nl-join": {

      "table": {

        "table_name": "t1",

        "access_type": "ALL",

        "r_loops": 1,

        "rows": 2,

        "r_rows": 2,

        "r_total_time_ms": 0.0181,

        "filtered": 100,

        "r_filtered": 100

      },

      "buffer_type": "flat",

      "buffer_size": "256Kb",

      "join_type": "BNL",

      "r_filtered": 100

    }

  }

}