/execute on attacker will not work if the entity has been previously targeted by the /data command that tick. This problem does not exist in version 1.21.4.

To reproduce:

1. /tick freeze

2. /summon iron_golem

3. Punch the iron golem

4. /execute as @n[type=minecraft:iron_golem] on attacker run say yes

   You say "yes"

5. /data get entity @n[type=minecraft:iron_golem]

6. /execute as @n[type=minecraft:iron_golem] on attacker run say yes

   Nothing is output

 The above situation can also lead to errors in datapacks and command blocks.