Government calorie advise misleading?

I'm in the UK and I largely agree. I think it goes to show that no guideline can be taken absolutely, although I would say that it does seem rather outdated and generic advice - but it's impossible to give a one-size-fits-all number given the variation in shapes, sizes and lifestyles.

The guideline actually does come pretty close to my requirements, I'm just shy of 6'2 (187cm) and hover around 190lbs. Factoring in some exercise, 2500 is about right, if not a bit low depending on how active I am.

But here's the thing - per Google, the average UK man is 178cm and 187lbs, he is increasingly sedentary and people with higher bf% require fewer calories than people with lots of lean body mass. According to the TDEE calculator, your average UK man, assuming 20% body fat and sedentary lifestyle, needs only 2200 calories.

The numbers perhaps need revisiting, but, just as is the case with BMI, it's incredibly hard to come up with a one size fits all!

The idea that an average person needs X calories, for a single specific numeric X, is just nonsense on the surface of it. We're different sizes; we have jobs ranging from deskbound reference librarian on phone duty to bricklayer's apprentice carrying hods of bricks and mortar all day; we have different hobbies, from watching TV all evening in a recliner chair to training for ultramarathons; and more.

I don't know what the context of your single-value average-man number is. That matters.

I'm in the US, not the UK, the US does use a generic average number for men/women in some overview-y publications, but also has more detailed and nuanced advice that is essentially TDEE calculator estimation territory, and much more nuanced. (One example: Body weight planner at https://www.niddk.nih.gov/bwp ). Those more personalized, nuanced estimates can differ wildly from the generic overview-y generality numbers.

The overview-y single number for men and women - here, anyway - is just used as an example. The other resources give more specific, personalized estimates. The estimates are about as good as any non-governmental so-called calculator is going to give, and probably better than some.

Any personalized "calculator" estimate, even an estimate from a fitness tracker, is still just an estimate, pretty much the average calorie need for demographically similar individuals. We're individuals, and we may differ from that average. Being far off from it is rare, but it can happen.

The most authoritative estimates comes from tracking calories as accurately as practical for 4-6 weeks, or 1 to 2 full menstrual periods for those who have them. The weight-change results can be combined with the calorie logs using some arithmetic, to get a personalized estimate. The calculator or fitness tracker estimates are just a starting point for that experiment.

The government "generic average woman/man" estimate is pretty much irrelevant for an individual who's calorie counting. I don't know how the UK's government sources talk about it, but here in the US, that's reasonably apparent to a person reading the detailed government recommendations thoughtfully.