Yes. Do you have a point to add to that? Do you feel there’s some reason he’s obviously wrong for example?
I find it personally revolting that people would assent to my own murder. I am the product of an unplanned pregnancy, and it is mere happenstance that I was not strangled, torn limb from limb, had my skull crushed, and my spine snipped apart at the nape of the neck, then carefully extracted piece by bloody piece, reassembled in a dish (to make sure that nothing was left behind to infect mom - abortions are "safe"), and dumped in a biological waste bin to be incinerated. I escaped that fate, but others do not, so I abstain from meat on every Friday of the year.
I do not understand why you and all the others would not assent to my grisly murder as an infant, as a 50-year-old, or perhaps not even as a feeble and helpless 96-year-old hospital patient, but you would readily take up the speculum and scalpel just because I had an umbilical cord attached.
That's a non-argument. People did all kinds of horrible things in the past (human sacrifice, cruel corporal punishment, slavery) and yet it is now obvious to us that these things are bad. I think it is safe to say that infanticide is one of the things that we don't need to debate in modern times.
At best this is an attempt at persuasion by “Everyone else is doing it and so should you.”
In fact, if something is perceived as horrible by most people in current society, I think the burden is on you to explain why and when it is justified. (So far your only argument was that people in the old times did it, which is no argument at all.)