You can't have an HR policy that discriminates against people for receiving mental health treatment from a physician, that is plainly illegal under multiple statutes both federally and in the state of California. This was not a situation where he was on ketamine while at work, and there are no accusations that his ketamine use even affected his work at all, even incidentally or indirectly. Even if it had, Netflix would be required to make a reasonable accommodation for him. But we know it did not affect his work because he received treatment in 2022 and Netflix only found about it in 2026 after he disclosed the treatment. Besides, he is a movie executive, it's not like he is operating heavy machinery. Ketamine is unlikely to have any effect on him that would in any way expose Netflix to liability.
Netflix seems to have simply assumed that all ketamine use is illegal and recreational, without bothering to conduct even the most cursory of investigations, which would have revealed that ketamine is in fact a clinically acceptable treatment for treatment-resistant depression. This is what happens when you have utterly incompetent idiots for in-house counsel and HR.