The issue isn't pedestrian deaths, the issue is that as a way to mitigate incidents, rail lines where the train runs on the street often have to operate significantly slower in the off chance that some guy jwalks. The reason I bring up the 510 is even ignoring the tight stop spacing, streetcars often travel far slower between blocks even if it can visibly speed up simply because of the concern that someone runs for it. The TTC in general has really strong history of slowing down vehicles as a safety measure to address some safety concern. This has happened on the 512, and especially on the 509.