Does the average hobbyist need a P bass - no.
Does a professional gigging and recording bassist need one - IMHO, yes.
Sometimes there`s simply no substitute.
In my experience with owning a successfull studio business and doing session work, a good P Bass always fills the void. in that I mean I have several styles of basses at my fingertips. A Thunderbird, jazz's, musicman... And whenever I not finding what I need to set in the mix, I pick up one of my Ps either with flats or round wounds and there it is. Of all the new Ps I've played and recorded, my custom shop Pino Paladino has been the best I've found for my taste.

No, not really.