I just researched the matter further. That article you posted above is primarily dedicated to critiquing one author. It references “multiple large studies,” but only links to one study posted on the exact same site. That’s a good way to know when someone is bullshitting you.

Their initial critique of this leading researcher’s conclusion was that he based his results on marriages in which the woman’s spouse had already left her. In fact, he did not. If you read The Guardian’s article on the topic, you’ll see that he also studied the physical and mental health of his subjects. That article was also amended in 2019 to recognize that he misread the data that the article you posted references.

More recently, other sites, including Psychology Today and Business Insider, have supported his initial conclusion. Not merely repeated it. Supported it with further research.

Happiness is itself subjective. Health outcomes are not. Accept those results if you prefer them.

I’m sure some marriages are happy and are beneficial. Certainly there are financial benefits. But we’re not talking about individual differences here, we’re talking in generalities, since that’s how research works.

Doesn’t mean you can’t build a happy marriage.