We're plagued with narrow sidewalks yet instead of optimizing the little space available we place obstacles smack dab in the middle. That tree belongs off to one side like the lamp posts. Toronto trees seem to do fine next to he curb on other streets so the salt argument comes off as weak. If it is, in fact, an issue the solution is to stop using salt or design protection for tree trunks .... not to compromise an already compromised public realm.
The work with the crane on Jarvis today (and next Sunday) is yet more HVAC work on the roof. I guess those judges like to keep cool!