They've said their thoughts based on their analysis. For me, I think that the $100k in this year is possible. Maybe it won't be exactly $100k but Bitcoin could attain a price as high as that. Also, do not really follow what these people say; do not make investments based on others' thoughts. DYOR and make your own guess (it's all guess work anyway).
The price will go down after this fast pump BTC experience but it will sure to increase again once correction happen since there will definitely many users who will secure some of their saving and there is still many users and companies who will adopt BTC. It's a continuous cycle, the only unknown is upto how much in can increase so we need to monitor it regularly.