A lot traders anticipated on the rise and always planned to sell before ignis. The rise was a certainty, the price of ignis is not. Dont fall for the iou tokens. Ignis pricecharts now mean nothing.
NXT price was over hyped by few whales and it stops pumping when those whales make their exits which followed by panic sell from newbie traders who have bought NXT at peak prices.
NXT was bought for quick profit before rather than to get free IGNIS airdrop.