I know working interviews can be illegal if they don’t pay you, but how much of a red flag should it be?

I have an interview lined up and was told it would be a working interview. Quick google search said an unpaid working interview can be illegal in California. As a prospective employee, is this an issue to raise during the interview? It seems like the kind of thing that could disqualify me as a candidate, though if it is the kind of thing that would disqualify me I have to wonder if this is the kind of organization I want to work for…