it doesn't take sophisticated hacking to breach even major systems
It doesn't indeed. There's a book published in late eighties, called The Cuckoo's Egg, by Cliff Stoll. It's quite a fascinating story by and in itself, and I highly recommend it, but the important lesson is that virtually nothing changed in this field. Targets might be different, vulnerabilities might be different, but the core of things stays the same - in the vast majority of cases, it takes patience and diligent work, not necessarily some kind of incomprehensible wizardry, to penetrate some kind of valuable information system.