It's going to be difficult to have this discussion without deriding the state of affairs in the US, especially in comparison to the rest of the world. I'm Canadian, so my points are through that lens.

The Gates Foundation is a private entity, so they're free to make whatever HR decisions they see fit. Realistically, 6 months of paid leave is still very generous compared to what's legally mandated. And their justification for reducing it from 12 months makes sense when you look at it from their perspective. They have work to do, and it's disruptive to have new parents leave, and be paid to do work that is unrelated.

Which is exactly why it's a shared financial burden when you look at other countries with paid parental leave. The benefit of paying a parent to take care of a new child is not seen directly by the parent's employer. Instead, that benefit is seen by the rest of society, insofar as the child is properly taken care of.

I'm a new parent, my son just turned 5 months. My wife is taking 18 months of paid leave, since that's become an option here in Canada. It comes at a reduced payout rate (i.e the same money you'd get if you took 12 months, but spread out over 18 months), so my wife has not met another mom who has taken 18 months. Furthermore, our new budget is adding 5-8 weeks of secondary parental leave that is only available to the other caregiver/parent.

There is a lot to do when a new baby arrives. Realistically, even though I didn't take time off, my productivity dropped, since I did my best to help out as my wife adjusted and healed. Furthermore, there is a lot to do as our son grows, to ensure he grows and learns enough to enter the education system by age 4. To turn him into a productive, functioning adult is 18+ years of work. As a society, we're asking every parent to make a significant investment in our future.

Therefore, it makes much more sense to socialize the cost. Paid parental leave should be provided by the government, not (directly) by the employer. And that support shouldn't just end at some arbitrary age cutoff. Sure, an 18-month-old is much more developed than a newborn, but my wife and I cannot imagine putting our son into daycare at that age. Instead, we're asking our family to take care of him until he's 2 years old. Then he's going into daycare, which we have to pay for out of pocket. Oh sure, there are some tax breaks available, but even when you factor that in, my wife's salary barely covers the cost of daycare. His daycare will cost more than my engineering tuition + housing cost.

My point is that in Canada, we've socialized the cost of the first 12-18 months, given some tax breaks for the 18 months to 4 years point, and then finally, socialized the cost of education when the child enters school. There's a gap there that should be filled.

In short, private employers cannot be expected to bear these costs alone, which is why most countries socialize it. We all know the US is way behind on this, and kudos to the Gates Foundation for trying to do something for their employees.

But this move is shortsighted, but it's endemic of the shortsightedness of our society as a whole. We expect everyone to be well-adjusted, educated, and functioning members of society, but are unwilling to bear the costs of supporting parents in raising children. Then, we wring our hands wondering why certain kids/adults seem to be lagging behind.