G# (13th fret), open E = Double stop.
A lovely sound. Then add a D at the 12th fret on the D string, a nice D7 shell. Then of course, all the variations.
Open strings are gorgeous for chordal pieces.
Fast chromatic runs down low, the open strings can be invaluable and at high tempo, the difference in tone wouldn’t be noticeable.
What about tunes played on a four string when a low E is needed? You have no other option, unless you retune.
Open strings are part of the Bass gig. At some point in your life, for some reason, there will be a need for an open string, even if it is just for tuning up.