SELECT yearmonth, COUNT(user_name)

FROM

(

SELECT LEFT(MIN(blocked.log_timestamp),6) AS `yearmonth`, user_name

FROM logging AS blocked

JOIN user ON user_name = log_title

WHERE log_type = 'block'

  AND log_timestamp >= '202107'

  AND log_type = 'block'

  AND log_action = 'block'

  AND TIMEDIFF(CAST(log_timestamp AS DATETIME) - INTERVAL 90 DAY, CAST(user_registration AS DATETIME)) <= 0

  AND EXISTS (SELECT 1

              FROM logging_userindex AS creation

              JOIN actor_logging ON actor_id = creation.log_actor

              LEFT JOIN page ON page_id = creation.log_page

              LEFT JOIN page_props ON pp_page = page_id AND pp_propname = 'disambiguation'

              WHERE log_type = 'create'

                AND log_namespace = 0

                AND COALESCE(page_is_redirect, 0) = 0

                AND pp_page IS NULL

                AND actor_user = user_id

                AND creation.log_timestamp < blocked.log_timestamp)

GROUP BY user_name

) sq

GROUP BY yearmonth

ORDER BY yearmonth ASC;