Depends on the band and the type of music.
In any case, I’ve learned to always have a back-up bass for a paid gig. Needed? Depends on your experience and level of professionalism. If you’ve never had an input jack go loose, or a pot short out, good for you. Try dealing with that when a club owner is paying you, when the band mates are counting on you, when the audience is watching and listening to you.
If you play in a band that does a variety of music and insists on getting close to the required tone, you may need one with flatwounds or maybe a Fretless. Let’s put them together just for simplicity.
Why don’t guitar players get questioned on this? Or do they? Altered tunings? Drop tunings? A tele, strat, LP?