I doubt Altcoins will fail - why? Well in my oppinion every coin has its support group and thats what all cryptocurrencies need. But mostly when the Bitcoin price rises, other coins fall in BTC value but not necessarilyin dollar or fiat currency value. As do they rise in BTC value when the price of Bitcoin drops.
It is how jt works due to people moving in and out different coins from and to Bitcoin.
Need I remind you that Bitcoin will always be the foundation of crypto and that can't change. It is thd first page of cryptocurrency and blockchaine technology.