As a father, when I stayed home after our second baby was born in 2005, and later when I spent time as a stay-at-home dad, there was something I learned very quickly.

I was pretty much the only dad doing it.

People will insist that this has changed dramatically in the past decade. But really, it hasn’t.

It is a remarkable, but simple, truth. I know that in general we’re still far from parity between men and women economically, politically, or socially. But still, for all the progress in terms of women advancing in politics and business, society still assumes mothers will be the ones to decide whether to stay home after a child is born and after.

And that means that even as we talk about trying to achieve more equity for women in tech, and in society in general, our culture still presumes it will be mothers, not fathers, who will put their careers and lives on hold for extended periods of time.

That’s why I’m hoping Mark Zuckerberg’s announcement last week that he’s going to take two months off after his baby is born will change the dynamic around a conversation that seems stuck in neutral.

“We’ve also been thinking about how we’re going to take time off during the first months of her life,” Zuckerberg wrote. “This is a very personal decision, and I’ve decided to take 2 months of paternity leave when our daughter arrives.”

Bravo. Yes, he has the financial means to make this decision an easy one in economic terms. But make no mistake, given that he’s CEO of one of the most important tech companies in the world, there would have been no second-guessing if he had decided to just take a few days off and then hop back to work.

By contrast, when Yahoo CEO Marissa Mayer recently said she would only take two weeks off after her twins are born in January, she was hit with another round of criticism.

“Since my pregnancy has been healthy and uncomplicated and since this is a unique time in Yahoo’s transformation, I plan to approach the pregnancy and delivery as I did with my son three years ago, taking limited time away and working throughout,” she wrote in a Tumblr post.

Just as happened three years ago, when her first baby was born, almost all the stories and cultural conversations have revolved around Mayer and her decision. What no one (or hardly anyone) asked then…or now:

Will Mayer’s husband stay home with the baby?

I pondered this question three years ago in a column for the San Jose Mercury News. There may be no better anecdotal evidence of how little our views on this issue have changed than the fact that, three years later, still no one asks, or even wonders.

Mayer’s husband, Zachary Bogue, is successful in his own right as a partner at the Data Collective VC firm. Still, surely she makes more money than he does. Wouldn’t it be logical for the person who earns less to take more time?

“The default position still seems to be that if a woman and man both have a job, it’s the woman who will take a step back and stay home with the child,” Brad Harrington, research professor and executive director of Boston College’s Center for Work and Family, told me when I spoke with him three years ago. “But it never seems to be the knee-jerk reaction to ask why wouldn’t the man make the same choice.”

Of course, how Mayer and her husband choose to make these decisions is none of our business. But, again, what’s amazing to me is less about the personal decision of Mayer and her husband. Instead, I’m amazed that then, as now, nobody even wonders about paternity leave. All the focus is on Mayer.

As I noted at the start, this is an issue of interest and fascination to me for very personal reasons. After our second child was born, I took three months off from work.

I was fortunate, because the previous year, California had become the first state in the nation (and still only one of 2, I believe) to provide paid maternity and paternity leave. The program allows for six weeks of paid leave at 55 percent of salary, up to a certain level. It’s not taxed, however, so the gap is smaller than it appears.

From a policy perspective, the legislation seemed like it would have caused a seismic shift in the question of leave for parents, and particularly, for dads. But it didn’t.

In a recent report examining the impact of California’s paid family leave policy from the U.S. National Institutes of Health, the authors wondered about the impact of the policy on paternity leave.

They concluded that so few men were taking advantage of the option in a meaningful way that they couldn’t measure it:  “This may have occurred because low rates of paternity leave use imply that we did not have the power to detect statistically significant effects,” the authors wrote. The policy did, however, double the average maternity leave from three weeks to six weeks. So, it was certainly a victory that families felt they could make this choice, economically.

A report for the U.S. Department of Labor in June 2014 detected an impact from the California law, but it was still fairly minimal: Of the men who took paternity leave, they increased the average of two weeks leave by a couple of days.

“Fathers typically take relatively little leave after a child’s birth, but California’s program has increased paternal leave-taking by amounts that, while small in absolute terms, are large in percentage terms,” the authors wrote.

Still, with paid family leave, less than three weeks (for men who use it) is compared to six weeks for mothers. And, of course, paid family leave is still a rarity in the U.S., though more Silicon Valley firms, including Facebook, which offers new moms and dads four months, have begun offering paid leave to employees.

Not much has changed since the summer of 2006, when I took a year off from work while my rockstar wife started graduate school. At the time, when I visited the playground each day with the kids, I was typically the only father.

The number of stay-at-home dads has inched up in recent years, but so has the number of stay-at-home moms (moms who don’t work outside the home) — from 23 percent of all mothers in 1999 to 29 percent in 2012.

By comparison, in a 2013 paper, researchers at the University of Minnesota found that the percentage of U.S. households with a stay-at-home dad had climbed from an average of 1.2 percent in the 10 years ending in 1979 to 3.4 percent in the 10 years ending in 2009.

“It seems that stay-at-home father households are not common for several reasons,” they wrote. “First, perceptions toward stay-at-home fathers as well as career mothers are negative. Both males and females appear to perceive working fathers and stay-at-home mothers more favorably than they perceive stay-at-home fathers and career mothers. These negative perceptions are embedded in gender role expectations that the non-traditional stay-at-home father households violate.”

The authors also note that because men typically earn more, there is more economic pressure for them to continue working. But the social pressure is significant, which is where I hope Zuckerberg’s example will help make a difference.

“Stay-at-home fathers are much more likely to be subjected to negative societal perceptions if they choose to stay at home than mothers who choose to stay at home,” the authors wrote. “To put it differently, mothers seem to have more leverage in choosing between work and home while fathers almost have no leverage and are expected to work.”

Of course, Zuckerberg isn’t saying at this point that he’s going to take a year off or quit his job or anything like that to raise the baby. But seeing a public figure of his stature publicly embrace paternity leave is still heartening.

To the extent there are still cultural, or self-imposed, taboos about men deciding to stay home with their kids, I’m hopeful that Zuckerberg’s example will serve to reboot the conversation.