If you can hold 4moa at 100 you can hold 4moa at 250.
Yes, stated as you have, it is technically the same, except the spread at 250 yards is much more than 4 MOA at 100 yards.
4 MOA at 100 yards = 4". At 250 = 10" and in the real world even more than 10" as the bullet is in flight longer which increases the effect of wind and the atmosphere. Add to that the difficulty to clearly see out to 250 without magnification and I think that is what Mr. Sage was referring to.