Economics teaches us that specialization increases overall efficiency. 2 people work more efficiently if they are doing different parts of a task and then handing it off to the next person vs both of them doing the same thing at the same time. This is why manufacturers use assembly lines for their cars rather than having several assembly teams that build the vehicle from the ground up.

So generally, if a group of people are all specialized to different tasks, they will perform more efficiently than a group of people all generalized and doing the same thing.

So let's apply this to marriage. Current culture views a lot of the traditional specialization as sexist, with the "ideal" couple arrangement being equally splitting chores and responsibilities and contributions. This is not the most efficient setup, and barely outdoes living separately (sure you share a space, but it needs to be larger).

The traditional (sexist and oppressive) model was that of a highly specialized setup, with a single male breadwinner and a supporter wife. According to the economic theory, this guy will be more productive than the equivalent guy whose wife also works out and is less able to support his emotional needs after he comes home. He will burn out faster and be less focused than the guy who receives the full support of his wife at home (and doesn't nag him about not contributing to her specialization).

So the real question then is if this difference in productivity is enough to make up for the extra income in the long run? Yes it's perfectly obvious that initially, you're going to make more money with 2 incomes than one. But considering the burnout factor, the marital stresses, the expense of hiring people to raise your kids, etc might completely offset the gains from having the extra worker. This is further supported by the lack stagnation of wages occurring over the past 50 or so years as female workers have flooded the market and people have had slower productivity growth due to higher stress levels.

And yes, I realize that it's "impossible" right now for many to live without the 2 incomes due to the aforementioned wage stagnation caused by the rise of 2 income homes (it's not actually impossible, you just won't be living the lifestyle that you want until you actually see the long-term results, if they exist).

Also, I don't care about the MGTOW arguments about family courts, etc. here, that gets discussed plenty. I'd like to focus on the equality vs specialization angle for this particular discussion.

TL;DR: Is one of the main reasons marriage looks like less of a good deal due to the decline of spousal specialization and the rise of 2 income "more equal" families?