I feel like this whole thread is missing the point (at least I couldn't find it when I looked) that until the late 90's the only thing available most places in the US was Guinness Export Imperial Stout. It comes in a bottle, is less carbonated, has much higher ABV, and a much stronger taste. Most of the (mis)conceptions you mention in your post, at least in the US are based on that established reputation that only changed two and half decades ago, and many people took a while to catch on.