The logic this author is using is "you will by definition traumatize your children, thus you shouldn't have children". Not only is this completely flawed logic, because even if it were true that by definition you will traumatize your children, that doesn't mean you shouldn't have children, but it also inherently says "you will traumatize your children". So they are basically telling you that you would be a bad parent. Isn't that offensive? I understand, every parent has flaws but that's not the same as "fucking up your children".
Apart from that, the "disgrace" remark comes from the inherent malevolence of telling people to stop procreating. Telling people to grow old living miserable lonely lives without the innate happiness of having children and being a parent. Having your own children that look up to you and (unless you are indeed a bad parent or if there is something seriously wrong with the child) will love you almost unconditionally. There is no joy greater than having children. Telling people to not experience that joy is in my opinion disgraceful.
I can understand the economic realities that sometimes prevent the opportunity of giving your children a happy life, but that's not what this author/person is talking about.