I think maybe one of the factors affecting Arranger popularity may lie in the fact that they tend to cover a huge range of styles and therefore only have a limited number for each particular genre. I travel extensively in the US and I find the music played and listened to in the US more homogenous than in Europe. That is, there is far more country/rock/pop played in the US (and sometimes it seems, little else). So if you’re limited to using one or two styles to please your audience then an arranger keyboard is going to be a bad bet. In an environment where a more eclectic approach to music styles is welcome and expected, the arranger is going to be a more useful tool – this may be true of much of Europe hence the higher take up of arrangers.
It was interesting that one comment on this forum a while ago expressed bemusement at ‘Country and Western’ being classified as a ‘World’ style on one arranger (Newsflash! It’s just one more ethnic style to the rest of us). Maybe that differing perspective says it all.
The difference may lie mostly in the audience expectations rather than the musicians. In Europe we have far less radio stations so they therefore have to cater to a wider audience by broadcasting a greater variety of musical styles. (This is changing in the last few years with the increase in the number of specialist stations starting up). On the other hand I have met many people in the US who never listen to, or are even exposed to, music beyond a very defined and narrow genre (partly helped by being able to listen to radio stations with a very limited style play list). As I say, this is starting to happen more and more in Europe and is to my mind a sad development.
Now before I get flamed by all the Americans on the board let me say none of this is meant in any way to be derogatory of US music or musicians; it’s just an observation. Indeed there are many glorious exceptions to this generalisation; hence the strong US presence on this board and the many fine American musicians and composers who consistently break the musical mold. Actually I salute those who bravely try to expand their audience’s musical horizons whilst having to please them at the same time (otherwise no repeat bookings!). For this job an arranger is the perfect tool.