A shiny new terminal is a fine place for high rent retail opportunities. Navaids on the other hand are an unnecessary expense, whose maintenance is a constant drain on resources.
And as I understand it:
New terminal = investment by the airport authority
New navaid = cost to NavCanada
Considering the transition to RNAV GNSS approaches, there's going to be very little appetite to invest in net-new ILS equipment, even though a large fraction of commercial aircraft in Canada cannot perform precision GPS approaches.