To answer your questions in short?
The ultra orthodox Jewish community. Williamsburg, Boro Park, Crown Heights, Flatbush. Like I said: reporting from "BROOKLYN"...
Israel, and the middle east in general as well HEAVILY use arranger keyboards for gigs like weddings, "bar mitzvah's", etc.
I know for a fact from talking to people here, there are YOUNG people buying keyboards all the time. From Psr s710, korg pa500 to pa3x and Tyros..
And the reason I say its not dying is because thank G-d the Jewish community is thriving bli ayin hara and constantly growing, AND one man band is a staple of Jewish life here. The average wedding hires a one man band, and, thank G-d, there are lots of them. This is partially I believe to limit the overall cost of the wedding which would be raised considerably were they to hire a full band.
Now DIKI, this is the reason we all use custom styles. Because we play unique jewish "hassidic" music, which, unfortunately the keyboard companies do not include styles for...
I'm saying all this to encourage you all, from first hand knowledge, that the arranger, and one man band business is not a dying but to the contrary, "thriving" here and in Israel and the middle east. Thank G-d.
That was exactly what I expected.Mid east ( iran/arabic/turkish)/mediterranian ( greek/labenese/cypress etc),Balkans and USSR,soutb EU ( Italy and Spain)some west EU ( Germany and even some UK) immigrant and 1st to 3 rd gen hyphenated ameican community living in US have mainly arranger use.( mainly in major cities like NY/LA/Ch etc)
Mid east and balkans especially.( ask the US retailers about their customers who buys TOTL arrangers - they will tell you it's mainly from immigrant community in US).Of course synthzone memebers are minority.Total synthzone members combined will be still less that arrangers users/buyers from Cairo or Istanbul or Tel Aviv.
The reason for TOTL or MOTL reason is sampling and 3rd party style support ( Korg /Roland/Ketron has major style sound support in there since local musicians create currenly or legacy ethnic styles) .Sampler is also common since you dont have good Oud presets are hard to find even in TOTL Korg or Ketron.