This kid does not care at all. He's been trespassed, banned for life, and arrested. He's not the only one. More and more are going to do this, and someone is going to get hurt. And then someone else is going to get sued.
A fence is the low-tech solution. An IR beam fence would be high-tech, but also might require that Disney security actually investigate breaches, so maybe not worth it.
The rumors are always that Disney parks have undercover security, LOADS of cameras, and some kind of SWAT team standing by. In reality, it seems they have, well no security beyond the bag checkpoints and metal detectors (and the new scanner things they're implementing).
I'll say it again-the lack of security that allows Sonswa to enter Epcot in the middle of the night will also allow a real bad guy to enter the same way. The same "security" that allowed him to skateboard WS will also allow real danger into the parks.