I think not, because no coin will be this much supported in this market. Everyone knows about bitcoin and if a new coin will rise up many people would still be loyal to bitcoin like me.
So its very hard to a altcoin to take bitcoins place in my opinion.
If bitcoin will go down altcoins will also go down and most of the time altcoins follow the movement of bitcoin.
The price of bitcoin will rise and that is for sure but we cannot expect it will be replace by an altcoins, let's just say altcoins have a limit and will not be more popular than bitcoin itself.