Yep. Fivers became common back in the late 80's, right? The Stingray fiver debuted in 1987, anyway. I didn't switch to fiver until 2000, but still had to wait years for traditional-looking five string P-basses to become available. The first I found was from Lull, then Sadowsky and Fender offered P-bass fivers.
Anyway, as you say, P-bass players tend to be traditionalists, and that's why the demand for 5 and 6 string P-basses has been relatively low.
I like the traditional sound of a P-bass, but I find the lack of low B string frustrating. You lose so many useful positions & options without it. Now, I never could get into a 6 string, but I'd love for Fender to put out a 6-string P in the Vintage Modified series, just for screwing around on.
nice.