Unless you have an on-premises child care facility that's physically separated from the office space, crying babies (which are very loud) will cause a great deal of disruption to the work environment.
Note that the author of this article is the CEO of the company, so it's not likely that lower-level employees will complain to her if they find her baby disruptive. I can't imagine that someone who's not the CEO could get away with something like this.
And what's going to happen if the parent/CEO is in a meeting with an important customer and the baby starts crying? Are other employees going to be expected to change the baby's diaper?
"Most of us are pretty much pre-wired to find babies charming and happy-making."
And many of the rest of us don't want to be anywhere near a crying baby - and yes, there are even women who don't like babies and don't want to have children. (The same can be said about dogs in the office - some love them, but some have been bitten by them in the past and would rather avoid them.)
Also I think for many people work is a rest from their kids.