Two things would work:
-Fix the fucking restrictive residential zoning regs. This is provincial turf.
-Build more public housing. This is also provincial turf, but the feds had been involved in the past.
The difficulty with point 2 is that there has to be an agreement between the feds and the provinces. If the provinces don't want to build public housing, that's the end of it. The federal government can't just barge into provincial jurisdiction because they feel like it.
In the article they're talking about the peak of federal involvement in housing being the 1970s. That's not coincidental, as it was prior to the patriation of the constitution. If zoning doesn't allow for the typical 1970s 3-floor walk-up apartment blocks, the feds don't get to overrule those restrictions.