No, it really doesn't. Even if someone had an ancestor who was enslaved, they probably couldn't so much as identify the group that enslaved them, and for the vast majority white people making this asinine statement, their ancestors CERTAINLY weren't being enslaved by the government they live under, nor were they being denied the right to be represented until a few generations ago.
>their ancestors CERTAINLY weren't being enslaved by the government they live under
Does they refer to the ancestors, in which case they often were, or does it refer to the present day people, which also describes slavery in the US.
>they probably couldn't so much as identify the group that enslaved them
Could the present day individuals of more recent slavery given an accurate identification of the group that enslaved their recent ancestors? One which wasn't stereotyping, and which neither excluded slave owners or excluded non-slave owners?
>nor were they being denied the right to be represented until a few generations ago.
They probably were. Voting was highly restricted in the past.