Nowadays all money which is moving between Bitcoin and altcoins is 100% speculative, so it makes no sense to try to make a rational discussion on which coin will prevail, since whatever happens now with the prices is disconnected from each coin's reality, being connected only to hype and pretexts for pump and dumps. Sad that it's turning this way.
Altcoins creates values in the market but this doesn't mean they will be against bitcoin. The market is a whole and they will grow up together.