It occurs to me that the 407 Transitway would be a very good environment for demonstrating low floor automation (among other things I rather strongly suspect that whatever the GTAA comes up with will be a single mixed busway/LRT corridor between Humber College and Renforth).I'll go out on a limb here and suggest that retrofitting our LFLRVs with autonomous tech might not be too difficult once the autonomous technology is available on the market. As long as the LRVs are fly-by-wire, it should be pretty straightforward to connect an autonomous driving system to the controls of the LRV.
The more difficult parts might actually the upgrades that would be needed elsewhere in the network. For example, all the network switches would need to be electronic, as they'll be no drivers available to manually move the switch. This won't be an issue on the Crosstown, but it will be an issue on the legacy streetcar network.
Electronic communications between Transit Control and the LRVs would need to be improved as well, as failed communications system would be catastrophic under autonomous operations. I'd image that some combination of cellular networks (4G, 5G, etc...) and mesh networking (essentially the streetcars wirelessly relaying messages between each other) would be sufficiently reliable. These solutions are proposed for use in autonomous automobiles as well.
It's exciting to think about the service improvements that would be delivered by autonomy. Operating costs would be significantly lower, which means we can afford to run additional trams. And without having to manage people, you'd no longer have to deal with layovers to switch drivers.