The lamb sandwich, orange juice and almonds alone could approach 800 calories, even excluding the other three meals. People are quite bad at estimating calories though, it takes practice.

It's typical in calorie tracking that people start the day strong, but then forget or lose will to track later in the day. Ideally days without a full record should be excluded; I'm assuming that's just not happening here.

I agree, but looking at the actual food eaten, it doesn't seem to line up.

Those recommendations are for people that are on their feet all day, not for office workers and home dwellers that never go to the gym.

No, you add more calories if you're active. The USDA has a breakdown by age, gender, and activity level [0]. 2400 calories is recommended for an adult sedentary male between 21 and 40.

Sedentary is now the norm in the developed world, so it would be weird to use active as the baseline for health recommendations.

[0] https://www.fns.usda.gov/estimated-calorie-needs-day-age-gen...

Estimations for roman soldier on the march come closer to 3000 calories.