300 is far from the smallest class at U of T. It’s more like 20. There’s only a small number of first year classes that have 1000. I know the first year psychology class does, but I’m not aware of others. There may be courses with a large total enrollment, but they are split into several classes. Just like high school - not everyone taking 9th grade English is in the same class. It’s not hard to reach out to profs. They all have office hours. They’re usually available before or after class, just like anywhere else. The only competition comes from being surrounded by other smart students. Everyone is just competing with themselves, not with each other.
UBC and U of T are similar. They’re similar size, and in similar environments - large, diverse cities. UBC won’t be as cold in winter or as warm in summer. Toronto is the financial center of Canada.
Don’t count on getting into Ivey. It’s very competitive.