It brings a host of other problems, though, like the inability for two people to play two completely different games at the same time if they were purchased on the same account.
Actually, you can use offline mode to get around this, it's actually even possible to play some games multiplayer over LAN with two computers on the same account... not that I've ever done that.
How about holding a button when turning on the computer?
The "hackers" who harassed Sony executives were random people from anonymous, and most likely, not hackers. The people who brought down the PSN are still unidentified. Lulzsec did hack and DDoS Sony, but it was nowhere near on the scale of the PSN hack. They did smaller stuff like hacking Sony Pictures/Music and releasing source code from the Sony Dev Network.
I wish people would actually know about the topic before giving their ignorant two cents, I mean, this stuff was being covered every few hours on news sites back then, if you had any interest at all (which you quite obviously do) you'd need to make a conscious effort to not see the details.