Nearly a tie: Canada and United States differ by barely 5%% in area — about 9,872,102 km² km² against 9,439,424 km² km².
Both sit in North America, so this is a same-region comparison: the new Equal Earth map draws both with the same honest geometry, and the real gap is exactly the 1× you see above.
The old map muddied it further: Mercator inflates Canada about 4.1× and United States about 2×, so on a Mercator-style map this pair appears 2.2× apart instead of the true 1×.
United States fits 1× into Canada.