"Streetcars and subway-like rapid transit lines serve different roles in urban transit:
streetcars are needed for their closely spaced, accessible stops in dense neighborhoods and higher ridership potential on surface routes, whereas rapid transit lines provide higher speeds and capacity over longer distances. Streetcars offer a more comfortable, accessible, and efficient ride on busy city streets, featuring near level boarding and a smoother ride than buses, making them ideal for connecting communities, even when operating in mixed traffic or with priority lanes."
The problem is that Toronto has currently the slowly tram or streetcar network in the world. See the video at
https://urbantoronto.ca/forum/threads/ttc-streetcar-network.27667/post-2260454 for why. It can be better, if the politicians, bureaucrats and others can remedy it.