One thing I would argue is that many modern gyspy jazzers are
disconnected from the american jazz tradition. I've called many trad
jazz tunes, like "Rosetta", and gypsy guys don't know those tunes. A
lot of guys are more like bluegrass guys carrying on a folk tradition,
rather than jazz musicians. The number of times I've heard the entire
1937 "Minor Swing" solo note-for-note on a professional recording is
insane.
I have always thought of gypsy jazz being rooted very much in that camp
fire, folksy tradition but not bluegrass. Some of the earlier gypsy
tunes, which don't seem to get played much, except by real gypsies (go
to Nice, S. France and you can still hear them on the streets). Martin
Taylor who played for years with Stephan Grapelli, has revived a few
tunes with an album (Gypsy Journey) featuring tunes like Typsy Gypsy.
These tunes have a distinctive flavour, that is more of a Flamenco or
Asian/Eastern/Middle Eastern sound, than American jazz related ...early
folk if you like, that followed the Gypsies on their migration from the
East into Europe, picking up influences on its way. I don't speak with
authority, but this it what to seems to me from listening to them.
Young gypsies players now are probably influenced by all sorts of
things, and may have lossed touched with the roots of the music
expecially of they are not of European gypsy extraction, but I don't
see anything wrong with that, as jazz needs to evolve. Unless of course
your gig is selling "authenticity".