This question is analogous to “why hasn’t anarcho-communism yet worked on a wide scale?” Which is a question with many, many facets to it. You’d have to ask a lot of questions separately.
If I were to try, though, I think the simple answer is “people who work in X area usually do not own the means of production and as such cannot redirect the end product to horizontalist organizations.” Most people can’t just quit their jobs to join a mutual aid group because, without being able to contribute things, the biggest thing a mutual aid group can pass around is time, and most mutual aid groups that exist irl are focused on doing tasks like “picking up prescriptions for others,” and cannot replace participation in the capitalist economy.
Nevermind how most governments don’t want horizontalist non-capitalist organizations to gain enough power to provide a viable alternative to living under capitalism.
Also, there's this idea that everyone has a shitty job. I like my job. I wouldn't do it for free, but I'm happy with it.
What's a mutal aid network? I've never heard of that before but you make it sound like it's a charity.
I only heard about them recently too so I might give an incomplete answer but
If you only recently heard about them, then why wouldn't you logically conclude that a plausible answer to your original question might be that more people don't join them because people haven't heard of them?
This seems like a no brainer so what am I missing?
People haven't heard of them.
Also, using the mutualaid.wiki resource you cited - I decided to look up what was available in my state and the only couple of groups seem to focus on Covid-19 related things....leaving me even more confused about what you're talking about.
I tried mutualaidhub.org - and found another one that is about 45 miles from me so I went to their site to check it out. From what I can tell, it's nothing more than a hyper-localized version of gofundme.com. It seems most of these things are just links to facebook groups. I don't think these things are as organized or as helpful as your original post made them out to be.
Also, for the record, I'm not actually looking for assistance. I've honestly never heard of this thing until your post and just am trying to learn more about them, what they do, who and how they help, and maybe find something I could contribute. These things do not seem like a very viable alternative to traditional social services.
Like a barter system or commune? That may be a good way to get homemade things, but you still need to pay (or get help paying for) basic utilities.
I just thought that was "being on good terms with your neighbors". My parents would do that at every house we lived in but I've never once talked to my neighbors and wouldn't think of asking them for help.
We call those cooperatives / co-ops where I am. There are a few food co-ops scattered around the city, but most of them rely on a "you work a couple of days a month at the shopfront" basis because land is obviously not something the urban poor can generally afford, and the produce has to come from somewhere. There are also a few DIY and repair co-ops and community centre sessions, but you have to be lucky enough to live near one or own/rent a car to really make use of them.
There are fewer formal food ones in rural areas though because of the tyranny of distance, it's more just a few neighbours sharing excess of their own crops. Transport is expensive or inaccessible so the rural poor don't get much selection of produce either, making it not overly helpful in comparison to charities. If everyone around you is only growing wheat because that's what the land grows best, you're not getting much non-wheat nutrition.
There's also the problem of accessibility. People with disabilities are frequently the ones experiencing the most severe poverty, and they may be unable to practically contribute because of existing barriers. Which leaves the eternal dilemma of "if they don't contribute is it no longer mutual aid?".
Food co-ops don't usually require people contribute labour and don't operate a storefront. People contribute to the co-op mainly just by purchasing through it. The co-op requires a minimum volume to be able to purchase wholesale and bulk goods. By pooling their purchases, co-op members provide mutual aid by making more goods accessible for less money.
Depends in part on where you are, probably. I've been part of a co-op that was deposit-based membership and workers didn't have to pay the deposit. Other co-ops I've seen near me but haven't been part of had work rosters. I suspect they all work slightly differently according to their individual contexts, it's not like they're franchised.
Because if everyone involved is quitting their jobs, they'll have no money with which to buy food. Which means they'll have to farm it themselves. And farming, even with top-of-the-line modern tech, is backbreaking fucking work. Also unpredictable as hell: bad harvests aren't uncommon, especially for novice farmers with no formal training like these guys would be.
In other words, one bad harvest, and everyone in the system you're proposing fucking dies. Yeah, there's a reason in the 1800s people were abandoning their family farms for the horrorshow of Victorian era-factories en masse: because even that hell was still preferable to farming.
Not to mention needing capital for the land, equipment, seeds, fertilizer, pesticides, fuel, power, storage, transportation and uncountable other misc with a price tag. Starting with trained doctors and on to even more narrow specialists.
At least where I live, people already help each other. They even build illegal things like working bridges. The result is the slums.