>> And large numbers of people cooking at home is a relatively recent thing

> I can't even imagine how anyone could think this was true, even in multi-generational upper-middle class urban families.

In the context of the sweep of human history of about two million years, people exclusively cooking at home being relatively recent is true [1]. Restaurants are a relatively recent invention [2] [3]. What we conceive of as normal meals is relatively recent [4].

Communal was the predominant cooking setting for many modes of cooking like baking for most of human history. This was because fuel was brutally time and energy-intensive to gather and prepare until our species started to master tool-making to a sufficient level that individual households at the mainstream level could afford the necessary tools. It literally took organizing a community to sustainably run much of what we take for granted in an individual middle class developed world household kitchen today.

Cooking over an open fire is likely the oldest mode [5], and that fire takes a fair amount of effort to sustain solely at the household scale, and the archeological evidence for humans routinely and widely making fire instead of sustaining it continuously suggests routinely and widely making fire is relatively recent (100's thousands instead of millions of years ago) [6], and even then it was common to borrow fire from a neighbor than making it, so arduous it was to make fire or expensive it was to acquire the tools. Our species only really started to relatively routinely cook during the Paleolithic age about 200,000 years ago [7], starting with open fire roasting, then proceeding from there (boiling came after roasting, ironic since boiling water is considered by us as how we start teaching children to cook) [7].

There is a simple experiment you can conduct today to validate this on your own: with nothing but a flint suitable for knapping (which in itself is an accomplishment to de novo achieve), and plain cotton clothing (to give you a head start), work out what it takes to start a fire, sustainably gather fuel, sustainably gather calories and nutrition, and scale it up to a minimum genetic variability group. It is incredibly exhausting, and prone to all kinds of failure modes.

The sheer amount of agonizing, brutal, incremental effort over the millennia it took our ancestors to "just" get to the stage to develop agrarian systems (and there is even debate if even that was a prudent choice [8] [9] [10], though for the record I'm pro-agriculture) is mind-boggling. By comparison, our current state of civilization is just LARP'ing "grinding", and gamers talking about grinding take that to yet an entirely different level. I give our ancestors their due: they were a set of some tough hombres, and we collectively do indeed stand on the shoulders of giants.

[1] https://food52.com/blog/17568-the-centuries-old-form-of-publ...

[2] https://www.history.com/news/first-restaurants-china-france

[3] https://slate.com/human-interest/2019/03/home-cooking-food-h...

[4] https://www.bbc.com/news/magazine-20243692

[5] https://www.newscientist.com/article/mg23230980-600-every-hu...

[6] https://www.livescience.com/when-did-humans-discover-fire.ht...

[7] https://lithub.com/why-and-how-exactly-did-early-humans-star...

[8] http://www.inquiriesjournal.com/articles/538/was-adopting-ag...

[9] https://www.livinganthropologically.com/archaeology/agricult...

[10] https://news.ycombinator.com/item?id=43118