I suspect developers are reducing the size of condos just to keep the prices somewhere in the range that people can afford. 

Toronto seems to be looking more and more like NYC where almost no one expects to own the unit they are living in. It probably has something to do with jamming more and more people into the same area. 

And short of mandating 'public housing' into every condo building, I suspect most families won't be able to afford those larger 'family friendly' units.