My idea is Altcoins also valuable. But not all. When the stable bitcoin at a high value again, Those altcoin relates to good projects are will be back with a high price. So no worry about that.according to my idea other altcoins will be useless in the future.
Altcoin is useless, please see ETH, it is the cause of BTC and crypto market to be fomo in 2017. However, I agree that the increase in BTC will make the market increase according to the price.