I have written my fair share of post-mortems with a conclusion of "my knowledge of the topic/domain was limited at the time of implementation and hence created

I have written my fair share of post-mortems with a conclusion of "my knowledge of the topic/domain was limited at the time of implementation and hence created issue X due to Y". It all depends on the organisation's culture, if management is always looking for blame you'll get meaningless incident reviews caused by fear, if there's trust you'll get a larger share of honest reviews with actionable points to minimising the risk of it happening again.