Is it just me or does the fretboard make much more sense on a 5 string bass?
Like easier to get an overview over in terms of chords, scales and intervals across the board.
Even if I play a 5 string bass for me the main strings are A D G.
The E string seems to be an extra-string, it doesn't sing as the other ones.
I mostly play a 7 string guitar (AEADGBE), when I play in duet, trio without a bassist, people hear a bass and a guitar, they wonder who is playing the bass.
So why a 5 string bass, I tried it and I liked it.
If you work with diagrams, mechanical shapes riffs and licks, oh yes ! It's useful !
About improvisation, sight reading... It's mostly useless.
But wait wait wait...
I play the bass in a big band, the first rehearsal I brought my 4 string bass, but there was a repetitive riff that wasn't uncomfortable, it was more comfortable on a 5 string bass.
So... Yes ! 5 string basses are great !