I don't know if this is a scam coin or not but what I do know is that prices for tokens, coins even Bitcoin fluctuate. So the fact that the price has dropped is not enough evidence that a token is a scam. I say do your due diligence.
There is no need to label POW as scam till December 1st 2017 when it is due for payout. The drop in the value of your POW balance can be explained in that as more people joined and take their own share then the value will definitely drop. What you have now may not be your final share it may still be lower. so bear that in mind.