1500 makes sense when its spain v. Aztecs, but when you start digging deeper you can pull out other much later effective start dates, like Jamestown was founded in 1607, and some inland regions weren’t settled for a long time - like the first european settlement in the great plains wasn’t until 1771.
So when I load up a game of England v. Lakota on the great plains is it 1500 or 1771? My point is it’s silly to care.