When people talk about sugar being harmful, they mean fructose. Sugar is used as a shortcut, but then some people mix it up or play semantic games by talking about other sugars.
Basically yes. Other sugars don't have nearly the same effect. It might be a blend of pragmatic reasons in combination with biology (not as sweet, more filling, etc) but the result is still that the focus is fructose.
I happened to speak to a friend this evening who is a biochemist
She reckoned refined glucose was the real bad guy, as it's what your muscles actually burn, while other sugars need converting first. Therefore its distribution within the body is unregulated - you eat it, it gets burned, no question. Contrasting the others, for which the conversion process serves as some form of regulation and is likely to run slower when you don't actually need it.
She also acknowledged fructose as a problem, primarily when its in corn syrup (or vast quantities of fruit juice) as you don't have to digest cell walls etc to get it. Whereas in fruit the absorption is slower (though for something juicy like an orange I can't imagine that much slower)
I'm sure this is an oversimplification and any errors are mine!
