exactly.

i've been gardening for years. it's a supplement. for like 1-2months i get nice produce that can feed a few people for a few weeks. but that's it. i maybe produce 20lbs of produce in a year if i'm lucky. that's over a dozen or two plants. i have a good sized garden of about 100 sq ft.

not to mention the weather any year could totally f you. one year we had three months of drought, so i got like 2lbs of tomatoes that year.

turns out i still buy like 95% of my produce from the grocery store... because it's available year round and it's hard to grow variety well unless you have multiple beds with differing soil and sun conditions.

most folks grow tomoatoes and cukes because they are easy and produce abundantly. but i am not going to live on tomatoes and cukes 365 days a year.

the space needed to grow squashes, berries, etc. is way way higher. you need a lot of land. and they are very low yield. a ten foot watermelon vine produces like maybe 1-2 melons per year and takes up 20 sq ft of garden space. a squash vine might produce 4-6 decent squash, etc. and a lot of veggies and plants are non complimentary, meaning they choke each other out if grown in proximity.

the only person i know who has a varied and big garden is an engineer who has spend five figures producing dozens of beds, water systems, and etc. and he still gets a shitty yield some years due to weather and he struggles constantly with rabbits, groundhogs stealing his crop. he has a whole trap and kill system for them even now. because the critters know he is the place to go for the tasty plants. most home gardening grow a few tomato plants and make some tomato sauce and throw a dinner party and that's the extent of their home gardening.

it's way more complex and difficult than some 'hrr drr just bring back victory gardens' nonsense. you're average person isn't going to be building a 1000sq ft veggie garden with fencing and dealing with all the part time job of labor and upkeep that it requires.