It has some benefits if they are worth or not I am not so sure.
It’s easier to change the routes, either permanent or temporally. In the case of temporally if it has a second source of power like battery or non electrical engine it can like use a non electrified street if there is some emergency or construction or whatever.
You can change routes for special days easily without junctions or whatever is needed for trams without big issues.
And even if it needs to electrify a new zone it, it probably much faster than the work for adding new rails and junctions.