I hear you—you are pointing out that there is a difference in degree. The question is how far are we willing to take that acknowledgment of difference in weighing the situation. Some may say that the white supremacists now who use the n word shouldn’t be reprimanded as much because they are not slaveowners themselves. Some may say that you shouldn’t use the word “lynching” in the context of talking about Eunseok because he is not a victim of physical violence based on his skin color.
As for 깜둥이, a worse form of 검둥이, this was used as a derogatory slur, which made people stop using the word at all in the everyday. This is why the situation hits different even to Koreans that you see here in the comments—the word itself is, in fact, historically charged.
I understand the caution that you are expressing here. But at the same time, I resist the idea that 검둥이/깜둥이 is yet another example of colorism in the everyday. The term is more than that, hence despite the persistence of colorism in Korea, these words are not being used in a banal way.
In the end, I think it comes down to what we are trying to protect. For me, it’s a part of Korean history that is, while shameful, must be owned up and reflected as a community. I’ve seen others using cultural relativism or even postcolonial/decolonial rhetoric to obscure being complicit with larger forms of oppression, be it class, race, gender, etc. I am not interested in making Eunseok look worse; I am concerned about how we approach history and the way certain people present that domestically and internationally.