Carmen Van Kerckove and Jae Ran Kim are criticizing a fairly common kind of statement among white parents who adopt non-white kids. It's not that uncommon to hear parents in such situations saying that they love their kids no matter what race they are, and it sometimes takes the form of "I don't care if they're black, white, green, or purple."
Carmen doesn't indicate why such a statement is offensive, but she quotes something from Jae Ran that is a reason. However, her reason seems wholly inadequate to me. She says it's merely because there are no green or purple kids. But there's nothing problematic about saying you would love your kids even if something were true of them that isn't true of any actual kid. There's no actual kid with six arms, but I don't think it's offensive to say that you'd love your kids even if they had six arms. So something more needs to be said to explain why this kind of statement is offensive. I have two suggestions, but at the same time I wonder if Carmen and Jae Ran are nonetheless being too critical.
1. There’s an ignorant assumption behind this well-meaning expression. It’s ignorant to speak as if color doesn’t matter at all. Color does have an impact. If this statement is supposed to be indicating that the parent thinks race doesn't matter in any sense, that is simply ignorance speaking. Also, it's going to be a rare white parent who is not in some way affected by having children who are not white. Most people imagine what their kids might look like long before they have any, and if that involves imagining white kids who look like them, then there will be at least some level of unmet expectations. If the statement is doing that, then it's a lie.
2. Another ignorant assumption seems to me to lie behind the statement. It treats any racial issues that might be raised by the race of their kids as if they are merely a matter of what color the kids' skin is. Why would it be relevant that the kids could be green or purple unless the mere fact of a different skin color is what might be problematic about race. But skin color itself is only our way of identifying and classifying people according to race. It isn't what causes any actual racial problems. So it's profoundly ignorant to speak as if red or purple skin color, which would be weird but doesn't bring any actual racially-loaded issues with it, is anything remotely like having kids of another race.
3. Some who say this may well be saying something that could be more explicitly put as follows. “I know it’s weird for white parents to have kids who are black or Asian or whatever, but I'd be ok with that weirdness. I don’t even care if their coloring is so weird that no other kid has ever had that coloring, e.g. if they had green or purple skin instead. I’d still love them.” The problem is that such a speech demeans the kids who aren’t white by treating them as ok despite not being white, and that does have a troublesome assumption. I can see how some who say this sort of thing really are assuming something like that. That reveals at the very least a kind of residual racism that sees non-white kids, even their own, as something they have to make an effort to love more than they might be expected to.
So I can think of at least three ways that this sort of statement is racially ignorant, demeaning, or otherwise offensive. But does it justify seeing it as entirely negative the way Carmen and Jae Ran are? I think not. There are several ways that something can be bad when it comes to race. One is that it stems from racism in the sense of a kind of hatred or animosity to all or most of the members of a race merely for being members of that race. That doesn't seem to be going on here. Another is that unconscious or ignorant assumptions or views affect what people do in a way that is bad. That is going on here. A third is that something produces negative consequences that have a particularly racial impact. That could happen in this case.
But I can imagine someone saying this in a way that involves only some of those negatives and in a way that is fairly unconscious and non-deliberate, while the person is at least well-meaning and wanting to overcome racial problems in this world. Such a person would be ignorant of some of the most important racial issues, but there's at least something admirable in the person's intent, even if there's something bad behind how they manifest it and even if it might lead to negative consequences. I think that in such a case we ought to acknowledge that well-meaning people can be infected with harmful ignorance and demeaning attitudes that nonetheless are not transparent to the person. Our moral evaluation of such people should be mixed and not purely negative.
Perhaps less common but surely more praiseworthy is the following sort of person. Suppose someone comes to understand the residual racism in their own heart. They realize that they unconsciously see black people as lesser than white people, realize this is wrong, and want to seek to overcome this unconscious response. They do not hate black people, perhaps sometimes fear them, and consciously decide to seek to do their best to change their inner response while trying to treat everyone well in the meantime. They even want to right inequities on racial matters. That's how convinced they are that racism is evil.
So one way they seek to overcome racial inequities is to adopt a black child, insisting that they will love this black child as much as they love their other kids. They then (somewhat ignorantly, as I've above explained) say that they don't care what color their kids are in terms of their love for them. They could be green or purple, even! Isn't such an attitude at least somewhat admirable? There's surely some badness mixed in with what's good in such a person, but isn't the desire to overcome racism a good thing? Isn't this statement part of that desire to overcome racism?
So I'm not sure every case of saying this sort of thing is necessarily as negative as Carmen and Jae Ran are treating it. I would at least view many such cases as decidedly mixed in moral status. Some harsh words may in certain cases be the best approach, but sometimes they may need to be tempered with a recognition of those admirable traits that may well be present.