In your examples, all the people caught in their bunker were high value or military targets facing an organized, mobile enemy. In a SHTF scenario you are likely trying to keep relatively disorganized looters at bay or stay unnoticed by larger forces. In that case a bunker that provides lots of storage room and comfortable quarters in a low profile is valuable.
Camouflage the silo and/or put a reasonably defensible structure over it and you may have the perfect place to wait out troubles. Make friends with your neighbors to keep some semblance of community and you will be even better off. Whatever you do, don’t be like Hitler or Saddam and bite off more than you can chew as enemies.
In a SHTF scenario, you don’t have to go around shooting at others to make enemies. Simply having food, water and a shelter will make you an automatic target.
A couple decades ago I was a member of a survivalist forum where much of the stuff was discussed. I learned a lot.
What you said in particular will get you killed: “Make friends with your neighbors to keep some semblance of community and you will be even better off.”
Once one or more persons know your setup, you are dead meat. When they get desperate, they will come knocking on your door as well as word spreading you’ve got food.
Even if you still live in a conventional home with your stash in your bunker, your neighbors will wonder why you are so well fed.