Trams should give way to road vehicles at intersections and vice versa if they need to. Otherwise, rather ugly intertwining like below can occur:
(https://drive.google.com/uc?id=1DElip0h5b0rh9htSU2e-iFB4M1ScgJGM)
Savegame attached. Using r8407 and pak64 120.2 with drive_left = 1 and signals_on_left = 1. The above intertwining happened at (43,55).
I have a feeling that this is not simple to fix but it would be nice if that happens.
That would completely ruin the usefulness of trams for me. I even think it is intentional, to avoid some problems caused by the conflicting scales of time and space.
It would also complicate the game code and lower performance.