This may be apocryphal, but I remember learning that in ancient Rome, street food was the only way for much of the population to get a hot meal, since they didn't have kitchens in the home. There are still places where cooking options in the home are limited, and dining out is the common way to eat (my friend from Singapore went through some culture shock in the US, since he was used to eating at street vendors for nearly every meal, and it was *relatively* inexpensive, probably because space is more expensive there than in the States). So there is definitely something to the hidden cost of kitchens, but it doesn't quite make sense in the US given our current housing options.
The middle ground may be connected to the growth of communal living spaces. As more people grow isolated in the "single family home" model, designed communities for adults and families are growing. These almost always have large communal cooking spaces, and often trade individual kitchen space for it (though most seem to still maintain kitchenettes of a sort, just not the massive kitchens we see in single family homes). Bonus efficiency: cooking for a crowd decreases the cost per serving.
But in general I think this is an argument against huge, wasteful kitchens, rather than an argument against cooking at home. I use an induction hotplate to cook 90% of my meals in my apartment kitchen. Maybe no huge Thanksgiving feast, but day-to-day cooking doesn't need a huge countertop and double-wide fridge.