Hmmm... My mum taught me to cook, and we had compulsory Home Economics in school (mid 1980s).
Any library has invariably got a whole rack of cook books, ranging from the very basic to the cordon bleu. Charity shops have inexpensive cook books - a friend who volunteers say that it's one of the things they sell the least of. And there's plenty of resources online as well. And community projects which teach people how to cook.
Fair enough, except that is already a hurdle; I wouldn't know where to start looking for cooking books; it's all a complete mystery to me; most assume a basic understanding of cookery which not everyone has.
Once I've found he books I need to know where to look for ingredients, figure how much I need, which shop sells what... and for people who've done a long shift and have a list of chores waiting this is more to add. Factor in transport to and from the shops, especially public transport, the cost of cooking when people are scraping together cash to put in the meter and it becomes a big part of a very busy day.
The same applies to online resources; you still need to get ingredients, understand quantities... For people who struggle with numbers that's a hurdle.
Can the hypothetical non-cook has/can afford the tools, bowls; sieves, and scales? that is an extra cost and more complexity. A one-off to be sure but still a cost. Charity shops sell kitchen utensils cheaply, if they have them.
If it's a choice of 30€ to buy convenience food for a week or a set of utensils, probably people will buy convenience food. I work with people for whom a 30€ loan over the weekend is a lifeline (although I have occasionally pointed out to certain individuals that if they stopped smoking/drinking they'd be better off...)
Assuming someone makes one meal, they need to know how to deal with the other potatoes, onions et c, or they go off and are useless.
And this of course works if people can read. Functional Illiteracy to some extent or another is surprisingly common, especially when it relates to a a mix of words and numbers and interpreting things like instructions. Immigrants have particular problems with this and if you can't read, a cookery book isn't much use.
Even if you can understanding most things, cooking introduces aa whole new vocabulary and when you have to keep translating words it's a royal PITA; I speak from experience here, and I'm fairly comfortable with translating tools.
Courses are handy, if you can afford the money for the course, ingredients, and/or time. And there's no language barrier. And you can overcome the social stigma attached to not being able to cook.
All in all, it's often easier to get a microwave meal; It'll cost in the long run, but many people in this position aren't thinking past the weekend anyway...