BFair22,

The trees you mention by the street curb, forming canopies, are on city land, the government plants and maintains those. But most trees in Vancouver are on homeowners' lots, about 80 percent of trees.

To understand the MASSIVE reduction in those trees in recent decades, you have to understand Feng Shui. In that belief system, it's bad to have a tree touch your house, and it is bad to have a big tree near the front door, and so on, for belief reasons to do with unwanted tree absorption of Chi energy and blocking good Feng Shui energy absorption, leading to breathing problems, so the beliefs go. 

Perhaps you missed the massive destruction of Vancouver's trees (see news below) from this? Because of this, governments all over the region had to suddenly implement new anti-tree cutting bylaws. 

NEWS

"In Vancouver, the tree canopy fell from 22.5 per cent to 18 per cent between 1995 and 2013"

"drastic decline in the... canopy since 1996, most... occurring on private property."