Clearly are going to need to fix the debris issue with a flame diverter or aggressive suppression. Obviously they didn't anticipate the booster eating through the entire concrete pad and boosting the beach into the atmosphere.
I'm pretty sure there were voices at SpaceX who predicted this outcome. We've been launching orbital rockets for over 65 years now, and every single launch facility for heavy lift vehicles uses flame diverters and water deluge systems.
It baffles me how anyone could even think that the most powerful rocket in history could do without these systems in place.
I can see why the idea of no flame trench is alluring. Imagine the capability to land a rocket on essentially a parking lot, refueling and taking off again. You could land and take off on the moon or Mars like that too.
But that's outdated by now. There's an orbital launch mount and once you need that you might as well have a trench too.
It looks like debris tore up the engines, which progressively lost more thrust and control authority as more engines failed, leading to the loss of the vehicle.