Due to the altcoin, Bitcoin still has not been able to get a full rise, because those new altcoins are drawing money from Bitcoin!
I think that's not the reason bitcoin hasn't increased because new altcoin has been born continuously since last year. If bitcoin was affected, it wouldn't set a record in December last year.
Yeah you are right and this is because Altcoin has more potencail than bitcoin, thats why people are converting their money from bitcoin. Demand for bitcoin is very low and so is the price. I do not see any pump in the price in this year. Hope that the next year will be good for bitcoin price but there is no chance for price growth in this year.