Well, if you apply extreme literalism to every single sentence you utter.
On the other hand, in the real world where people actually speak languages, there are these things called "idiomatic expressions" which do not have the same meaning as the literal words, yet are understood by all fluent speakers of the language. If I say in Spanish, "Todo el mundo entiende ese" it doesn't LITERALLY mean that every single one of the current 7+ billion inhabitants understands what I'm saying; what it means is that a huge majority of people conversant with the subject at hand understand it. If I say in English, "The fifth time he asked me that, I hit the ceiling" it doesn't mean I climbed up on a chair and pounded the ceiling with my fist.
In the context of popular music and jazz, the word "solo", especially in the context here where a group is playing and we're talking about "what happens during the bass solo?" the IDIOMATIC EXPRESSION "bass solo" does NOT mean everyone else must stop playing and the bass plays completely alone. In this context, which everyone else participating in this conversation has understood perfectly, the word "solo" means that the instrument in question is featured, in what's usually an improvisation, while the rest of the band provides some kind of background accompaniment. Granted, sometimes the whole rest of the band drops out: that's called in jazz parlance (which is NOTHING BUT idiomatic expressions) "strolling" or "laying out".
I assure you that if Charles Mingus had said during rehearsal "You know, Dannie, during my solo I'd like you to keep straight time the first couple choruses and then go into that triplet thing", Dannie Richmond would not have responded with "Well, you know, Charles, actually the word "solo" means "unaccompanied" so I'm not going to play at all" - not unless he wanted a punch in the mouth.