Parental leave suggests leave for more than just the mother and is in fact what you explicitly said "provided parental leave for both parents when a child is born".
Which seems valuable for many reasons. But I would be interested in seeing data which supports that this results in better health outcomes for mother and child. However, I'm not sure this specific case tells us much about the general case of patients (you cited CF) being cared for by friends or family members...
You're not backing up your statements with data, and not making a reasoned objective [1] logical argument... people do that all the time of course. But it doesn't really help advance a discussion or change anything. It's probably why you've ran into issues getting your point across in general.
[1] You might feel you have sufficient subjective reasons to believe what you state. But it doesn't help convince others, for that objective proof is required.