According to the query I ran in T356631#9512754 on db2153, the column cul_type on cu_log incorrectly has a default set. The correct type of the cul_type column is VARBINARY(30) NOT NULL and instead on db2153 the type is varbinary(30) NOT NULL DEFAULT ''.
The full output from db2153 (for reference):
wikiadmin2023@10.192.0.4(enwiki)> show create table cu_log\G
*************************** 1. row ***************************
Table: cu_log
Create Table: CREATE TABLE `cu_log` (
`cul_id` int(10) unsigned NOT NULL AUTO_INCREMENT,
`cul_timestamp` varbinary(14) NOT NULL DEFAULT '',
`cul_type` varbinary(30) NOT NULL DEFAULT '',
`cul_target_id` int(10) unsigned NOT NULL DEFAULT 0,
`cul_target_text` blob NOT NULL,
`cul_target_hex` varbinary(255) NOT NULL DEFAULT '',
`cul_range_start` varbinary(255) NOT NULL DEFAULT '',
`cul_range_end` varbinary(255) NOT NULL DEFAULT '',
`cul_actor` bigint(20) unsigned NOT NULL,
`cul_reason_id` bigint(20) unsigned NOT NULL,
`cul_reason_plaintext_id` bigint(20) unsigned NOT NULL,
`cul_result_id` bigint(20) unsigned NOT NULL DEFAULT 0,
`cul_result_plaintext_id` bigint(20) unsigned NOT NULL DEFAULT 0,
PRIMARY KEY (`cul_id`),
KEY `cul_timestamp` (`cul_timestamp`),
KEY `cul_type_target` (`cul_type`,`cul_target_id`,`cul_timestamp`),
KEY `cul_target_hex` (`cul_target_hex`,`cul_timestamp`),
KEY `cul_range_start` (`cul_range_start`,`cul_timestamp`),
KEY `cul_actor_time` (`cul_actor`,`cul_timestamp`)
) ENGINE=InnoDB AUTO_INCREMENT=878564 DEFAULT CHARSET=binary ROW_FORMAT=COMPRESSED
1 row in set (0.000 sec)