no, top alt coin will be synergy with bitcoin, when bitcoin up it is also up, and when bitcoin down it will goes down. however there is no way alt coin will replaced bitcoin, satoshi nakamoto still a legend
In short time, really not have any altcoin can replace Bitcoin with the momentum growth like now. But after 5-10 years when the cryptocurrency world's stable, Bitcoin will have many competitor can replace it anytime if Bitcoin don't improve it's system.
the thing about bitcoin's competition is that so far nobody has created anything capable of competing with it. and the worst part is that i think they are not even trying anymore!
back in the early days when altcoins started coming out like LTC, NMC, XMR,... these were trying to give something different and do something worthwhile to compete.
but the new altcoins are just aiming for the profit, to become more expensive even if it means a short life. the dev and early investors become millionaires and kiss crypto goodbye! this is not a competition any of them have any remote chance...