Walk-in traffic doesn't generate high enough ridership, the residents along the Sheppard corridor have their mode share split with car (Hwy-401 is next door) still, and despite all the condos that have gone up, actual trip generation have remained low since none of these condos have any office or employment component to generate outside trips.
A two-station extension to Victoria Park is interesting because this would intercept the Victoria Park bus, and the Consumers area has many offices and employment that would generate trips from outside the corridor.