Yes. I think it does excuse it. If the US does X and expects everyone to accept it. Then Country Y doing X is excused… how else could it be? Any other way leads to disadvantage of Country Y
The original point was that if a country is doing something now, that can be an excuse for another country doing the same thing now.
If you want to extend your excuse to "a country did something bad 50 / 100 / 500 / 1000 years ago (and later regretted it)" then you need to provide extra reasoning for why that still works as an excuse for what a country is doing now.
Edit: I'm guessing from the downvotes that I didn't make my comment clear enough (or I didn't understand the comment I was responding to). My intent was to point out the logical gap in an argument that could be seen as justifying China's genocidal policies.
That's taking it way out of context of the original point.
There isn't a lot of evidence of China doing that (your X). I expect Xinjiang will jump to front of mind for people, that is largely a "Mass Incarceration of an ethnic group"... which while not at all what my original point was, there is definitely an element of hypocrisy from the US here... But unlike travel restrictions, I don't think my original point holds.
