I know people who farm for themselves and frequently have a surplus of vegetables on about 50m2 of land.
I bet you a beer they don't grow olive trees and grains enough to feed themselves in 50 Square meters.
Do that and you end up with a big clay garden pot that'll grow anything.
But yep, that's the game with agriculture, long term steady work to improve conditions, soils, drainage, mulch pits, septic lines, fruit trees, etc.
I've got a video somewhere of me hitting the ground on our block with spade in the summer and it bouncing off like it hit solid concrete, crazy stuff.