They're a niche (ERB vs. 4 string), inside a niche (bass guitars vs. guitars). Not exceptional in the sense that everyone knows what they are, but I still reckon 5 (and more) string basses will be outnumbered by 4 strings in the wild at least 5:1, maybe even 10:1. Dogma is difficult to change.
I know it's a super parochial view of things but right now in my house it's 10-0 in favour of 4 strings, and over all time, the score is 56-2...