Got to looking at this website, which shows what day of the month Thanksgiving has fallen on (or will fall on) between 1990 and 2020.
Apparently it always falls on November 22nd at the earliest and November 28th at the latest. I guess it just feels like Thanksgiving should come between November 22nd to November 25th, any later than that seems...late.
U.S. Thanksgiving is always the fourth Thursday in November.