[osmo]

The western edge for downtown in Toronto is Spadina. For all the major east west streets try become more transitional west of Spadina.

In the east it is Sherbourne as nobody considers River street downtown. Parliament is a good comparable to Bathurst IMO for the east end. The transition points are important as less intensive uses and structures find a good place in these areas

City planners created the Bathurst to the Don River thing. On the ground it isn't what is there now. Locals from the old Boroughs also tend to get lazy and will call anything from High Park to the Don "downtown".

Toronto has a massive downtown as it is. Some parts I only ever see once or twice a year. I don't remember the last time I was at Avenue and Bloor for example.