The very real challenge for the employers, though, is that as you said demand is slowing down ("it seems fewer people are doing big home reno’s."). If you raise wages and therefore cost of the end product (the renos and builds) then demand sinks even lower.

And when demand was crazy, you have the opposite problem - there were so many customers who would be willing to pay through the nose to do reno work/new builds that contractors/builders took on more than they could handle and ended up trying to hire anyone with a pulse; unfortunately no contractor/builder wants to be the guy saying "no" to new work because they want to "make hay while the sun is shining" knowing the market could turn (which it eventually did).

IMO the only way this gets fixed is for demand to stabilize...and trying to achieve that would be a really arduous task and probably starts with sharply lowering immigration rates and sharply increasing social supports that encourage higher birthrates + changing building regulations to incentivize family-sized apartments and condos.