Pondering the Danforth tree-trashing

A friend alerted me when he saw paving crews ripping out the raised-bed trees, wondering why the destruction? We wondered, too, so Danica and I went to see.

Obviously the removed trees were goners, never to be replanted as was done when Gerrard was paved. How come?

Something WILL be planted in the new beds (left), now at ground level. And look at the remaining trees, still in their boxes. The root base is a couple of inches narrower than the box. Why the gap?

This much is clear. Toronto loves and protects its trees, so there ought to be reasons and plans for the greater good of our canopy. It occurs to me that our last harsh winter was deadly to many trees in planter boxes. There just wasn’t enough soil to insulate the roots, so they froze to death.
Maybe a decision has been made to stop putting trees in planters. They need to be in the ground, as I found myself with a front yard cedar. Ground, good. Planters, bad.
It remains a mystery to me, though, why decades-old trees could not have been saved and replanted. I wonder too, what’s going to happen to those planter trees that seem to have been readied for movement (that gap around the root ball). The destroyed trees were in an older style of planter box.
But then, the survivors are in newer style boxes that sit on top of newly paved sidewalks. They seem to have been repositioned, after the recent repaving. They look healthy. Maybe they will stay and the gap will be filled with soil. There goes my no-more-planter-boxes theory.
Time will tell, but for now I have more questions than answers.
[Update] I found some information here.