Tbh I suspect that 1800 calories for women is nearer the mark for many than 2000. It's a reflection of a changing lifestyle.
2000 calories per day is way over what I need. It's easier to increase from a basic intake on the basis of being bigger or being more active than the reverse. Just add a bread roll or another side or desert.
For context, if you do an individual calculation for my height and weight (I'm a health BMI 5' 2" and currently 8stone 4). I think my recommended calorie intake 1400 for little to no exercise. For moderate exercise it comes in at 1700 calories per day and it's only very heavy exercise that puts me at 2100 calories per day.
I probably clock in as needing around 1500 to 1600 most days in reality. I do consciously think about it now though I don't actively calorie count.
1400 calories a day is actually pretty difficult to do if you eat a lot of ready meals because the portion sizes are set this average of 2000. By definition of being average, it's really not serving 50% of women to set the average portion based on 2000 calories a day. Psychologically you are taught to finish what's on your plate and it's incredibly difficult to leave food.
I like to use the example of going into McDonalds. What should I order, if I eat three meals a day? Should I have a grown up meal of a quarter pounder meal or should I tuck into a Happy Meal? When I say a quarter pounder meal is roughly 1000 calories whereas a Happy Meal is 500 does it make it easier? Yet over the years the comments and looks I've had for doing it are pretty dreadful. (Socially it can be challenging and I've had snide comments before about it).
I wish restaurants would do a wider range of 'small bites' as a rule tbh. Instead plates just seem to get bigger. I also don't want to eat 'diet food' or 'kids food'. I want the same things just in a more sensible portion size. It's definitely a culturally related thing and standard portion sizes do differ considerably depending on where you live.
The 9 inch plate diet is the only one I adhere to for good reason.
This is why I REALLY don't see anything sinister in this recommendation for this reason. There is some psychology in there, but also some awareness of people who overestimate / exaggerate their exercise and how lifestyles have changed to rely more heavily on ready meals and eating out too. It's an injection of realism imho. People don't cook from scratch as much as they should and it's easier to cut the recommendation of calories than change those habits.