I tend to agree, but I think the limits apply to voicing regret for having specific children, especially in front of said children.
I think about the most sickening thing that anyone has ever described to me is meeting somebody who, in front of his own (tween and teenage) children, referred to them as basically a regrettable burden foisted upon him by his wife. It's bad enough suspecting that your parents don't care for you, I'll bet it hurts more to know for certain.
Still, it is nuts to receive backlash for saying that it's incredibly hard work. Of course it's hard work!