Depends on the location. If done right, trams can be the single most efficient form of intra-city transit. Treating trams like cars is not doing it right.

My city has trams that are grade-separated from car traffic for most of their routes, but often run alongside cars within their own "lanes". Cars can still use that lane for maneuvers and overtaking, but whenever a tram approaches, it has the absolute right of way.

Tram tracks are much narrower compared to bus-sized streets. They can run through places where roads can't be built, and bypass busy intersections. They're also quieter, less disruptive (see: grassy tram tracks), less polluting (no asphalt dust or tyre particles), more durable, and more efficient (steel rolling on steel).

Trams usually don't have to care about ground clearance. This allows them to be built with a much lower floor. Running on fixed tracks also allows them to perfectly align with the platform at stops, which makes wheelchair accessibility trivial.

Unlike trolleys, trams can use pantographs to connect to the overhead wires, which is much simpler and less likely to fail compared to trolley poles, which require switching whenever the routes diverge, and can get caught on the wires. They also don't have to carry backup batteries or combustion engines.