Because too many "natural health" people don't understand actual health risks.
Botulism pops up because "<flavor> infused oils" became a thing and people started dumping uncooked garlic into them. And then a bunch of people got sick with botulism because a low salt, neutral pH, anerobic (the oil blocks oxygen) environment is practically tailor-made for incubating botulism.
"Classic" recipes for preservation generally make sure to have salt, nitrates, low pH and little oil/fat (and generally a combination of them). Guess why? Most pathogens don't like salts (curing) or acid (most canning). Some of the worst (like botulism) don't like oxygen and oil/fat can block oxygen.
You can even see the ignorance in the comments here. Some people were talking about putting non-acidic things in a vacuum seal without a pressure boil (240-250F). No. Bad. Very Bad.
Take a look at things playing out in "raw milk" right now. "Pasteurization" was hailed as a breakthrough for a reason--it is.
I hate the "industrialization" of our food chain as much as anybody (I simply cannot find a tomato that doesn't suck). However, you solve that by breaking up the cartels--not by wiping out food safety.
As for nitrates, a lot of the problem is the fact that the "industrial" process pumps the meat with a LOT more nitrates than people would use at home. When properly cured, most of the nitrates in meat have chemically reacted and there is very little residual. Industrial processes worry more about running out and so pump the meat so full of them that there is a ton of nitrate still left in the meat even after curing. It is this unreacted nitrate residue that seems to "cause problems".