The problem is twofold - despite the city pushing for three bedroom units, they are often the last to sell - the market is rather limited for that product (that isn't to suggest there may not be a market in the future, but the fact is they don't sell well today).
The criticism that the three bedroom units are too small is valid - but there are affordability factors at play - with $psf approaching $700 on average downtown, the unit sizes are shrinking to pull the end selling price down to affordable levels - if you wanted a more reasonably sized 1,000 sqf three bedroom unit you are looking at a base price of $700,000 - toss in a parking spot and a few upgrades and you are easily in the $750,000 - $800,000 range - for a family there are plenty of ground oriented housing stock options with a small backyard within close range of the downtown core in that price range. I'm not suggesting that there are no families that would want to purchase that $750,000 condo, but realistically given the choice in that price range most families that could afford a $750,000 home downtown are going to look for a ground oriented option in the communities immediately surrounding the downtown core.