They are more of a black box - but humans are a black box that is perhaps more studied and that we have more experience in.

Although human behavior is still weird, and highly fallable! Despite best interventions (therapy, drugs, education), sometimes they still kill each other and we aren't 100% sure why, or how to solve it.

That doesn't mean that the same level of study can't be done on AI though, and they are much easier to adjust compared to the human brain (RLHF is more effective than therapy or drugs!).