Used to. There used to be slaves, but it does not mean that it's acceptable to enslave people now. While slavery and saying "the Ukraine" is not the same, the latter shows the clear lack of geopolitical knowledge.
I understand the point, and I think it is good to correct people when they refer to Ukraine incorrectly.
However, comparing a (typically accidental) prepended word to slavery makes me recoil from your argument. I think it is similar to "Reductio ad Hitlerum"[1]. People who refer to the current country as "The Ukraine" are incorrect, but saying that they are implicitly supporting the history of that name is overreaching.
I don't think most westerners even associate anything particularly problematic with a prepended "the". It's used in "the Netherlands" for similar historical reasons; like the Ukraine, the Netherlands was a descriptive term for a certain region before it was a sovereign state (the Ukraine meaning the borderlands, and the Netherlands meaning the low countries). Whether it's retained or not when the region became a sovereign state seems more or less arbitrary.