Thanks kitty and Ludi.
Another advantage is I am HUGE fan of ease of storage. I only "can" fruit and pickles. I adore apples because you don't HAVE to do anything except store them correctly. Likewise I have a huge preference for vegetables which can be simply stored (potatoes, squash, onions, carrots etc). I've never home canned vegetables. I've frozen surpluses but mostly we never seem to need to eat them anyway because we have so much stored or fresh.
Likewise meat. I've pondered getting a pressure canner but I don't know if the extra trouble would be worth it, especially for just two of us. I don't even know anyone in NZ who ever home-canned meat. I think it's because we're in a place where there's always been fresh meat easily available, especially sheep.
I think for us, if we had to have meat, it would make more sense for us just to keep meat chickens or rabbits again. It takes the two of us about three days to eat a whole chicken as it is,
Forgoing meat altogether would mean making sure we gathered all the nuts and sunflower seeds rather than just a good quantity of them like we do now. Nuts and seeds are very easy to store.
As a system for someone in the right circumstances this would be such a simple, easy system. Use fresh and stored vegetables. Use fresh and stored nuts and seeds. Keep laying hens (also easy). Focus on apples for fruit (easily stored). If you didn't have access to water canners, pressure cookers or freezers, I think it's certainly a methodology to think about. You could see meat and milk products as optional additions if you could get them. I'd have to process the peaches, pears and other easily perishable fruit though because I do see that as part of our staple diet in our case.
Still I think nuts, seeds, fresh and stored vegetables, fresh, stored and preserved fruit and fresh eggs could be a very good system for some people as the staples of survival. Nothing to stop them adding extras through foraging, bartering and so on to top it up.