I find myself doing 1-finger per fret low down, but with some movement of the hand too. Not a huge fan, though.
I've been thinking about what we mean by a "Jazz Bass". The sound of the bridge single coil does nothing for me, so Is it still a "Jazz Bass" if I replace it with a humbucker? Harley Benton (Thomann) makes the MJ-4 (link) which has a MusicMan style humbucker in the bridge position. Is that still a Jazz? If I had one of those, or any cheaper J-type, I'd replace the electronics and would look for a humbucker for the neck position. (DiMarzio makes a split humbucker for Jazz, for example.) Still a Jazz? 🤔