Rails are too restrictive for real life. I trust a self driving fleet to respond immediately to an emergency by stopping. Maybe causing a disruption but very little loss of life or property.
https://www.wired.com/story/cruise-fire-truck-block-san-fran...
Until we do a better job of solving these issues, we need to have backup drivers available in these vehicles, or, the vehicles should be operating in places where dumb breakdowns don’t block ambulances and fire trucks.
Yes they don’t go everywhere, but in the UK we aren’t very spread out in our cities, towns and even suburbs, so it’s reasonable to expect quite a large number of people to be within walking or cycling distance of a tram stop.
You can do just fine on rails.
Sure, if you want to get into the rural mountains you might need to rent a car. But like, for most people rail will do you just fine.