I just don't think you're going to effectively compete with big agtech by putting a bunch of parts in a box, shaking it, and hoping you end up with a beautifully integrated solution. Integration hell is the reason big commercial firms dominate when it comes to large integrated systems.
If you want to see a couple of guys learning how to farm from scratch, visit https://www.youtube.com/@spencerhilbert. Spencer and his brother made a bit of money off games and Youtube and have been starting out on corn, hay, as well as raising beef. It gives a pretty good insight into how pervasive tech is in farming, and how despite that, how much of farming still relies on hard, physical work.
> raising beef
Is that cows? English isn't my first language, so I thought beef was the word just for the meat, with all Normans eating while Saxons raising thing.
However, I'm not as interested in being a farmer at that level. I'm much more interested in the homesteading aspect of farming. I'm not trying to feed the world as much as me and mine and maybe some extra. So not just farming, but also some ranching with sheep/goats/chickens/pigs. I have friends doing this that I'm keeping an eye on. They had a head start as their kids grew up in FFA and are already familiar with raising live stock, and then having them processed to make that part much less daunting.
So a DIY solution is aiming for somewhere in the center of the market -- enough scale that it makes sense to bother, but not enough enough money to avoid the headache of DIY. It might make sense for some mid-sized farms in developing economies, but it seems to be a narrow window to me.