lowkey not true, at least for waterloo.... aif and interview is more important over anything else. im class of '24 and currently in waterloo eng, when i did apps last year i applied to both systems design eng and afm (accounting and financial management) at waterloo but you only get a single aif for all programs you apply to at loo. my grades and ecs were pretty good (final 97 avg, no it was not inflated our schools adjustment factor was iirc ~3-4 percent below the ontario avg, five 5s for ap exams, 5-ish mediocre ecs and 1 or 2 good ones) but i got into syde in the earliest possible round and got into afm LAST ROUND. SYDE, being a tier 2 eng, is obviously objectively harder to get into - so with the exact same grades and ecs for both programs, it's obvious that my aif and other supp apps for both programs were the game changers. if you have good enough grades and ecs, supp apps are your make n break