I can see the reason. It gets confusing when the same name describes two coaches. I like the idea of separate names myself. Besides, it was out of sequence. At the time the pecking order of DPs was Kountry Star, Dutch Star, Mountain Aire while the gassers were Dutch Star, Kountry Star, Mountain Aire. The switch between KS and DS made it more confusing.
If I recall, when the Dutch Star was dropped, the Scottsdale came out and was it's replacement. So it was just a name change. They've redone the product lineup again this year so I'm not sure what goes where any more. They now have more product lines that cover all of the bases - some people even feel that they cover too many bases.
There's new high end coaches like the King Aire and the FRED based Grand Star have joined recent entries like their toy hauler.
They even have a new entry level model called the London Aire.