Science

here's the study: https://www.sciencedirect.com/science/article/abs/pii/S0165032725024346

all the co-authors are Chinese and the main author is associated with:

Department of Nutrition and Food Hygiene, Ministry of Education Key Laboratory of Public Health Safety, School of Public Health, Institute of Nutrition, Zhongshan Hospital, Fudan University, Shanghai, 200030, China

They don't seem to disclose who funded the study, they claim the funders did not influence the design of the study, but then they also claim they did not have any specific grants from any public, private, non-profit, etc. sources.

The study just analyzes an existing data set, and all it does is show the same J-shaped curve that is commonly found with many things, e.g. the same thing they found in this study with coffee consumption is found with alcohol consumption:

https://jamanetwork.com/journals/jama/fullarticle/2443580

Setting aside population risk, any clinician who has tried to counsel a patient about alcohol use has encountered the question: “But I thought a couple of drinks a night is good for my health?”

...

Three examples—alcohol consumption, body mass index (BMI), and blood pressure—help elucidate the challenges posed by J-shaped curves. With respect to alcohol consumption, a meta-analysis of 34 prospective studies, pooling findings from more than 1 million individuals and almost 100 000 deaths, showed a J-shaped relationship between alcohol intake and total mortality.1 Consumption of up to 2 drinks per day in women and 4 drinks per day in men was associated with lower mortality than zero consumption, with about one-half drink per day associated with the lowest mortality risk.

BMI and blood pressure are more complex risk factors not solely based on consumption, as with alcohol. BMI is a simple, if imperfect, proxy for energy metabolism—and therefore the current standard for representing healthy weight. A prospective study of 1.46 million white adults demonstrated a J-shaped association between BMI and all-cause mortality after adjusting for potential confounders, including smoking and alcohol intake.2 All-cause mortality was generally lowest among those with BMI of 20.0 to 24.9 and higher on either side of that interval.

tl;dr it's not that it's healthy to drink a couple drinks a day, or to drink a few cups of coffee a day; it's more like because the average person consumes that much alcohol or coffee, the data we have is skewed and the outliers who fully abstain or over-indulge also happen to have worse health outcomes

being average is what is being tracked here, not that moderate alcohol consumption actually improves health outcomes

this is like the finding that any running no matter the mileage or time spent running massively improves health outcomes - that's based on correlation studies that found people who identify as runners tend to be more healthy (because being a runner is associated with people who have higher income, better access to healthcare, etc. - not because running an insignificant amount actually massively improves your health).

This is a science and medicine communication issue. The take-away is absolutely not that drinking 2 - 3 cups of coffee is better for your mental health.