it's kind of insane to me that this is seen as insane, if I'm honest

Yes, I agree. That's probably why hintymad shared the context of not being raised in the US.

The cultural difference doesn't seem like something to "cringe" over. I also don't think the hyperbolic use is restricted to the US. Pretty much any english speaking country will use "insane" to describe something with emphasis. Certainly normal in the UK and Australia.

> I also don't think the hyperbolic use is restricted to the US.

Strictly restricted? Of course not. But for what it's worth I've been told by numerous Europeans that they perceive casually throwing around extreme hyperbole to be characteristically American behavior. I guess it goes with waitresses pretending to love you.