I spent a few years living in a city outside of the Greater Toronto Area and somehow managed to be a Toronto Zoo member for a good portion of that time. I would board Go Transit near the end of the line, travel to Union Station in downtown Toronto, take the Go train along Lakeshore East, and then take a bus from there to the Toronto Zoo. And then I had to do the whole thing in reverse to get back home

. How long did that all take? Perhaps, I suppressed the memory because I can't recall.
No doubt, I am a little crazy, and others wouldn't go to the same lengths. Well, excluding Judache, who will suffer through long public transit commutes as well. I certainly would have liked to visit the Toronto Zoo more while I was living in southern Ontario. It's hard to say how much of a difference shorter travel times would have made though.
A visit to the zoo, isn't the same as a visit to the grocery store or a commute to work. For the latter, convenience is the most or one of the most significant factors in your decision making. Visiting the zoo is a special leisure activity. The Columbus Zoo was built to the north of the city of Columbus and has been immensely successful. The Minnesota Zoo has done fairly well and it is about as far from the city centers of St. Paul and Minneapolis as the Toronto Zoo is from downtown Toronto. The Minnesota Zoo also has to compete with the Como Park Zoo and Conservatory. Yes, travelling time will impact the desirability of visiting the zoo, but as long as it's nothing crazy -like my trips from outside the city- then most people will put up with it. I don't think that the greater ease of travelling to the Calgary Zoo is enough on its own to explain the four times greater ability for the Calgary Zoo to draw visitors -as a function of metropolitan population- compared to the Toronto Zoo.
Years ago, I spoke with one of the original designers of the Toronto Zoo and the subject of location came up in our discussions. It was believed that the Toronto Zoo would be of international statue and that this would create enough of a draw to help compensate for its new location outside of Toronto's center.
For many years, the Toronto Zoo was well-known throughout Canada and I remember seeing commercials for it when I was growing up in Alberta. At that time, the Toronto Zoo was Canada's undisputed top and most popular zoo.
Times are changing and the Toronto Zoo can no longer lay claim to that crown.
How does losing that crown affect Toronto Zoo's reputation in Canada's biggest and most famous city, and outside it?
I would argue that for the Toronto Zoo to thrive they have to show some ambition! That doesn't mean that they should spend extravagantly. It also doesn't mean that all the projects have to be massive and splashy. Little improvements add up. What I think it means is that things should be done at high standards and with the intent of creating a premier facility. If the Toronto Zoo can do this, admittedly not an easy proposition, I am confident that they can challenge again as Canada's most visited zoo!