In my opinion, it is unreasonable. If somebody comes out and says "I am being constantly harassed by my colleagues, this makes my life hell and I think it's also illegal" and you respond with "well, according to the legal precedent from 1925, Snowflake et al. vs Ontinence, Inc., making your life hell is not illegal unless they put a live rat into your drawer and it bit you, and since no evidence of rat bite has been presented, clearly the whole complaint is invalid" - that's not a reasonable way to treat this complaint. If you're a judge considering a motion to dismiss, sure, that's exactly what you'd do. But if you're a reasonable person reacting to a complaint that somebody's life is made hell, then no, the legal precedent of the Snowflake case is not the main thing you should reasonably discuss. You may be more worried about the "hell" part.