No altcoin will ever replace Bitcoin because it is a scarce asset that has global trust running for years. Most alts gain their value from the implication that they can gain more BTC from their alts.
and knowing that they only rely in BITCOIN PRICE?how come they will overpower a currency that is almost fix in rank number 1.
bitcoin will remain in this position for another 10 years again or more maybe .altcoin on the other hand?will struggle more and more but wont get any chance for hanging in the top.