The reason we only see the unsophisticated attacks might well be that the ones that are carried out professionally are never caught. If I was China and intent

The reason we only see the unsophisticated attacks might well be that the ones that are carried out professionally are never caught. If I was China and intent on this kind of cybercrime I wouldn't put all my eggs in one basket, but would try different avenues to get to my target. Resources don't seem to be a problem since it's apparently government backed. I would see this as the top of the iceberg, and expect there to be more sophisticated attacks hiding out there that we might never know about.