This is interesting. I've had borderline low copper lately and it may improve because I no longer take Vitamin C and Zinc. It may also have to do with my history of eating a lot of fruit and fruit juices.
Personally, I don't think 1 or 2 pieces of low fructose whole fruit daily is bad. It's a good idea to know which foods are highest in fructose and avoid them, especially in large amounts. Citrus aren't very high in fructose, or bananas, or melons. What I think are highest in fructose are honey, dried fruit such as dates, figs, etc., apples, grapes, pears, etc. I think it might be best to avoid foods that have high fructose in relation to glucose. Honey and molasses are beneficial for their minerals, so we have to weigh the pros and cons.