People underestimate the value of decent family benefits and the cost of child care. The benefits of having a stay at home parent breaks even way sooner than people think.
Depends on where in the world you are. Pre-kindergarten-daycare for a toddler costs about 300 € where I am, so two working parents are taking home way more than they have to pay additionally.
That isn't an ad hominem. That would be if they called you stupid. It's actually a very reasonable discussion point to ask if you have personal experience with this topic. This is a situation where having kids is probably important to make a well reasoned argument.
Kind of ironic how you - instead of responding to the question asked - went into attack mode. There was no attack in there at all. In order to respond to the point made, it's important to know if it is a point made from personal experience (as a parent) or from a theoretical standpoint of a non-parent. It does not invalidate the point itself, yet changes it's perspective.
My answers will be different if there's a fellow parent with different life experiences than me or if there is someone who's seen parenthood more from the outside. Both change nothing regarding the validity, yet your reaction to a dentist telling something about teeth would be different than your reaction to a maths teacher telling you something about teeth, wouldn't it?