I understand that, but as someone with serious mental health issues (and actually hospitalized over it—so a top candidate for being a possible offended party). I understand insane is an outdate term, and hardly refer to it as offensive. "Psycho" (any bf that calls their gf this is about to regret it) or "erratic" (less hurtful but gaslighting) is far more offensive in tone and in rudeness, if someone called me either of these in real life, I'd be insulted, where as the term "are you insane?" can be mused as a person who likes very spicy food/is an adrenaline junky, and no one tends to be hurt emotionally.
It is also used in a game (and is used in story telling) as a stereotype—such as pirates (as no modern day pirates even come close to the stereotyped theme "Pirates" and even era pirates is hardly accurate, it is clearly fantasy/story inspired).
The term insane/mad is really more story and fictional themed these days, IMHO, unless this is the vernacular to offend those with mental health issues regionally. But to me insane, mad/madness or certifiable are just so old, and generalized terms they hold no weight to offense. I honestly, only used Insane in Sims 3 for my Alice in Wonderland themed Sims as they were the most apt and did not offend me as a person living with mental health issues.
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