Hasn't all of history gone in the opposite direction? People used to be more "self-reliant", and then when something unexpected happened, say, crops failed in a

Hasn't all of history gone in the opposite direction? People used to be more "self-reliant", and then when something unexpected happened, say, crops failed in a region, millions would die and millions more would have to take everything they had and migrate somewhere with more opportunity. If you need something, and it exists in the world, what fundamental advantage is there in having that thing be off limits? Or in having the burden of providing placed on a few rather than many?