I highly doubt that Apple wil lose customers. They continue to increase sales.
The 4th gen ipod came out 3 years ago. It has had two major software updates - ios 5 and ios 6.
Just because you got yours a year ago, does not mean that the 4th gen is only a year old - it is a three year old model.
Yor ipod still does everything it did when you got it and does more than it did when it came out.
This is nothing odd or unusual at all for any software driven product.
The 4th gen ipod simply does not have enough RAM to handle IOS 7.
They have forgotten no one.
They have provided updates for the ipod touch for the past three years - that is a long time in technology terms.
The 4th gen ipod has been much improved with two major updates. how many updates would make you happy?
The fact is that the ipod touch 4th gen simply cannot handle ios 7. Would you prefer that they dumb down the updates so that a three year old device can run it? Would that be fair to those who paid for the most recent models?