Doing the calculation isn't hard. It's harder to know how much energy (be it electricity, gas, or whatever) you actually use. It also varies wildly with meals, as some need multiple stove tops (is that the right term?), possibly for varying lengths of time and/or the oven.
Please note that you can not really deduce the energy consumption from a power rating, as those usually are max values and not what it'll actually need.
I have good enough energy monitoring that I can measure the usage (sort of), and having rather high electricity cost at around 0.40 €/kWh I do pay some attention to it. Running the oven for like an hour will be roughly 1€. Boiling water for pasta or something is probably more like 20 ct (includes cooking the pasta). Just using a lid actually helps a lot here if you make use of a lower power setting after reaching a boil and putting in the pasta.
It's gonna have to be a very elaborate meal to break 3€. So while it does matter and add up, compared to buying fully prepared food from a restaurant, it isn't that dramatic even with very high energy prices like these.
Cooking appliances use a lot of power, but they don't run for whole days at a time, so the energy used also isn't that dramatic. There's a relatively recent video by technology connections that goes into detail, and might be of interest (link).
I understand that. You said "I think it means" and it is not at all what it means. It's probably what they want to say by using these words, but isn't what they (the words) mean. It probably is where they (the authors) mean. And that also isn't what you said either, hence my comment.