There's a huge difference between the TTC and the MTR. TTC runs buses trains and subway while the MTR primary operates subways, electric rail and a smaller scale light rail system. Unlike cities like NYC or Paris where there are multiple lines running in parallel within a walkable distance, MTR only have a line where millions of riders would funnel into a nearby station. There's no duplication of service. They simply don't have anything like an U on Yonge and University or in Montreal where the Orange and Green line serves the downtown. That would eliminate extra maintenance and operating cost. They rely on longer trains and better line management. Hong Kong doesn't really have any "suburbs" either. Everywhere the subway reaches is developed into a smaller city core with a decent density. So it's not possible to clone their system and expect it to work here. HK is so gridlocked and pretty much impossible to own a car, everyone would either resort to the subway or be late. Manhattan have similar gridlock issues thus they have ridership on their subway. The issue is too many old and low capacity lines.
It's also good to note that MTR is a much newer system than the TTC but the original lines are reaching 40 years old and reliability is degrading. Being privately operated, of course they are taking better action than the TTC. I think in 20-30 years, they would see more reliability issues as tunnels reach 50-60 years old. Subways don't last 100 years Robbie!
