They knew....the only preparedness was never More than evacuation....you’re not going to stop lava flows as this.
N9, but you can do permits differently, mandate certain unsurance requirements, build infrastructure to better address mass evac needs, plan sheltering and other requirements better. Heck, if they’d allowed only rich folks who have the financial means to relocate to live there, they’d be better off.
BTW, reports of a 19th fissure, this one a few hundred yards long and hocking lava loogies....