Even something as permanent bollards is enough to alert pedestrians "hey, something is important here, because of these posts in the ground, maybe I should look around and be more aware"
Maybe they could have lights on the top that flash red when a streetcar approaches.
Also audio of the same guy for visually impaired that says "walk sign is on for all crossings" at Dundas/Yonge could say something like "warning streetcar approaching"
I know this seems like a lot, but that is a very touristy area, no amount of "informational" awareness campaign will work because so many people coming into the city who've never been here.