Or make life harder! Quit the elevator. Quit the automatic transmission (and car). Quit the online shopping.
Making some progress with self-checkouts and pointless lineups at airports.
Less jokingly (hard to outrun a bad diet) but more pedanticly: drinking less (alcohol and calorific beverages) might be a better start than eating less.
It seems that a largely sedentary lifestyle free from exertion matches both.
It would be insightful to see the sensitivity analysis for BMR with respect to strength, activity, muscle mass, ect.
I know there is a body of data about environmental hormones and BMR, ect, but my understanding is that the impact is barely measurable with large sample sizes. I expect that it can't hold a candle to activity. In my personal experience, my BMR can easily modulate by 1000 calories based on body composition and behavior. That is a huge impact.
"It is also possible that the long-term reduction in BMR represents methodological artefacts. In the early years, measurements of BMR were often made using mouthpieces to collect respiratory gases, and recently such devices have been shown to elevate BMR by around 6%. A second possibility is that early measurements paid less attention to controlling ambient temperature to ensure individuals were at thermoneutral temperatures."
lower testosterone = lower lean body mass (you gain tens of pounds of muscle on TRT even without exercising)
lower lean body mass = lower BMR. an average doughy 200 pound guy and a 200 pound athlete have vastly different caloric requirements.
The authors suggest that the decreased consumption of saturated fats over the last 30+ years is likely to contribute to the reduction in basal metabolic rate and gains in weight. The mouse model component of the study provides some support.
Why it's dropping is still a n mystery though.
Nevertheless, the solution is still the same: eat less.
The study: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10445668/