The Yamaha Workstations are routinely used in professional touring situations, being handled by roadies, loaded in and out of trucks on a daily basis. You really cannot compare the Arranger user with a workstation user. Arrangers are still considered home keyboards by many players and the Manufacturers agree.
Name one major band that tours with an Arranger. They don't need them. Again the him user and the demographic are older people. I am retired and work PT in a music store. More young people ask for the Motifs. No one ever asks to play the "arranger" We don't even stock a Tyros. The local Guitar center does not stock one Arranger.
Yamaha knows this and knows they will sell everyone they make because it does not look imposing and "industrial" I think they make it out of plastic frankly to make it look like a "toy" so their market will not be intimidated by it.
You must realize todays arrangers are yesterday's Lowery organ. not yesterday's Prophet 5.
Yamaha Tyros 4
Yamaha Motif XS8
Martin DC Aura
Breedlove ATlas Solo
Bose MOD II PA