The end of the article said that family got stuck in the attic and the water rose higher than the roof, drowning them all. That's why.

Depending on the roof construction it may not be that easy. A true least not without tools. And then you're very likely to end up trapped in there and drown if the water level comes up over your roofline

If you have no roof access from the attic, and the water level rises, you are stuck.

After you've gone through the 3/8"-3/4" plywood/osb that's nailed on well enough to not come of in a hurricane?

My attic at least has several layers of plywood between the airspace and the felt. Probably why you see footage of rescue teams trying to get to the attic from the outside... with axes.