Throwing something sized the same as TCM into location like this kill it not due to the proximity to TCM but location.
Although retail properties carry a higher value assuming full occupancy, building condominiums there will be a sell-out which is better.

SS2 square is very much convenience & services based, a mall at the size of SSTwo Mall shouldn't compete in that way, period.
Atria is not doing very good but because it is surrounded by so many shops you hardly don't notice its existent.
SSTwo Mall's location is worse, Jalan SS2/72 was never really that busy.

Knowing who owns the mall and who made the decision will tell you clearly why it doesn't work.
Jaya One being at the busy Jalan Universiti took a long time for people to actually remember its name, albeit it is largely due to its 'far-sighted' internal layout.