The classic advice goes something like this - in a survival situation you will be killed by the first critical problem you can't solve yourself. Communities form for a reason and knowing the geography of your operational area includes the social geography.
1. Some people have trust issues, possibly to a clinical level. They don't trust their neighbors to not be zombies etc knocking at the door to take their stuff. Ironically, when you spread awareness of preparatory issues through community building, you reduce the chance of that happening.
2. Some people are overly focused on one or two particular scenarios and 'optimize' their and preparations on those scenarios. E.g. A real-life neighbor has CBRN gear, firearms, and food but doesn't have a chainsaw or basic hand tools.
Like most stereotypes, the lone preppper has some truth associated with it. It really comes down to definitions. I'm not prepared for TEOTWAWKI by any means, but if I lose my job, or we get hit with a hurricane, or my car dies, or my house burns down, I've got reasonable contingency plans for those. Am I a prepper?
Dogs can help. There is a trade-off to be had. Larger dogs can actively participate in defense, but they require lots of food. Geese might be a better option; they seem to be happy eating grass.
Don't be an easy target.
Gun guys aren't liked here but if somebody is going to get a nasty surprise it would be the bad guys.
If you are a hard target bandits will most likely choose another one.
If 10 people really really want your food and supplies, they will burn you out or crash a vehicle into your home, or drop a tree on it. Alone you are nothing, you are much more in a community.
Think minute men vs a lone wolf. It is no contest.
See https://www.monolithic.org/ for the right way to build. Crashing a vehicle does nothing. One of those homes, at the bottom of a hill, withstood a run-away 18-wheeler with only cosmetic damage. Fire could damage a layer of insulation, but only if the dome isn't covered in stucco or better. Get the impact-resistant windows plus shutters, and get the tornado-resistant door.
Don't get me wrong though, since guns are extremely useful for defense and most of the bad guys aren't very tough. Surviving without a community in a serious scenario is just impossible.
It's not often. Having ten firearms and a million bullets doesn't help you much if you're a semi-crazed loner who vastly overestimates your abilities and usefullness
That's why meatspace social networking is part of prepping for some people: they recognize that, if there is a collapse, the way to survive isn't just to have stuff for yourself, its to have a well-prepared tribe. To be (well, hopefully kinder and gentler than the title sounds, for most preppers who take this strategy) the Blood King, rather than worry about him.
We have a pretty long history of plague, famine, war, and other "apocalyptic" scenarios, and in almost all accounts, people tend to help each other, and most would die of hunger rather than steal from an innocent person.
The main problem is that what we are very good at is building narratives that portray some class of "others" as not-so-innocent, and therefore, deserving all the pillage, rape, and murder we can muster. That's variously the neighboring nation, some minority ethnic group, political opponents, the rich, the clergy... you name them, there's some brutal revolution or war targeting 'em.
So, basically, the worst-case scenario is ending up on the wrong side of the pitchfork if / when the revolution comes. Something that, quite frankly, the Silicon Valley should be mindful of.