What about 1920x1080 (16:9) vs 1920x1200 (16:10) and 2560x1440 (16:9) vs 2560x1600 (16:10)? I have seen it as the norm that height gets added rather than width

What about 1920x1080 (16:9) vs 1920x1200 (16:10) and 2560x1440 (16:9) vs 2560x1600 (16:10)? I have seen it as the norm that height gets added rather than width subtracted.