As part of a healthy diet, fruit is good - wonderful indeed for the vitamins, minerals and enzymes it contains - but it does need to be balanced with other food groups. For some people it works best eaten on an empty stomach - away from other food - because largely it is a high(ish) water content food and the body can best absorb its nutrients when it's eaten alone. It can also be best digested, in this way, for some people. Those who believe in a food-combining ethos suggest that it can sit in the stomach too long when eaten with other foods. Try it for yourself and see what works best for you!
It's true that we shouldn't eat too much sugar but wholefoods - i.e. in this case, fruits in their natural form - are wonderfully nutritious and, for most of us, shouldn't be avoided. Anything eaten (or drunk) to excess isn't so great! Balance is the key - variety is good - also eating seasonally is desirable and sensible. Additionally and especially, it makes sense to avoid too much fruit in the concentrated fruit-juice form.