Bitcoins price movement generally affects altcoin prices. The relationship isnt always predictable, but there are some common trends.
I think Some people want to be rich in Bitcoin and some people want to be rich in dollars. So you need to see what you want to do and then decide how to play cryptos for your benefit. For me, I like Bitcoin and Altcoin because they give us more freedom than what traditional financial markets do.
Many great Bitcoiners buy and trade cryptos so they can increase their bottom line Bitcoin.