I do not think Altcoin future is in the traditional banking system though Altcoin future will partly depend on the success of Bitcoin. The future of finances and investing would be totally different from what we are seeing to presently! Cryptocurrency will be running in parallel to fiat and cryptocurrency would probably win because it smart, effective better and cheap!
At the current trend we can say that it depends on the success of bitcoin, but I think altcoins has different purpose, the moment
people get educated and begin exploring the altcoins there is a potential that the dominance of bitcoin will decrease.