The keyword here is "intentional community", and there's a long history of people trying to make it work and sometimes succeeding nicely.
But neither farming nor technology is key to making it work. The challenges in decreasing order of size are: interpersonal (requires a lot more collaborative effort and management of drama than you'd expect); legal/administrative (you still need to pay e.g. property tax & comply with building codes & farming law); cashflow (you still need to buy from outside, especially if you're hightech); and only then the day to day of growing food (which may be more labour than you or the community is used to).
On the <100 people scale it's like having roommates who are also co-workers. Hence the tendency for intentional communities to come with some level of cultishness to ensure the community sticks together without being pulled apart by individuality.
But neither farming nor technology is key to making it work. The challenges in decreasing order of size are: interpersonal (requires a lot more collaborative effort and management of drama than you'd expect); legal/administrative (you still need to pay e.g. property tax & comply with building codes & farming law); cashflow (you still need to buy from outside, especially if you're hightech); and only then the day to day of growing food (which may be more labour than you or the community is used to).
On the <100 people scale it's like having roommates who are also co-workers. Hence the tendency for intentional communities to come with some level of cultishness to ensure the community sticks together without being pulled apart by individuality.