The issue is that you can't prepare for everything. Having extra food and water, sure. Maybe buying a generator so you can use electrical equipment, that's generally useful. But, aside from that, your preparations for a flood will be very different from your preparations for a military invasion, which would be different from preparing for a pandemic.

Also, the more extreme your preparations are, the more it matters when you pull the trigger and activate your emergency plans. If your preparation is simply having a cupboard with extra toilet paper and some extra canned food, it's no big deal to pull that stuff out if the store runs out. But, if you have some kind of bunker in the mountains, it's a bigger decision when to "bug out" of the city and go live in the mountains. You're basically quitting your job, so if the emergency is something like the COVID pandemic, when do you decide things are so bad that you can take that extreme step?