I don't know if you agree with me but if you are familiar with a gear shift you truly are. Understand what I mean. Gearshift is a device used to engage and disengage gears in any type of transmission of mechanism. Bitcoin in my opinion does the same in the crypto space. Whatever the performance of BTC in the market also altcoins are affected. It is bitcoin that directs the market status which is good to some who are real and bad to that althat'shatise just there for nothing except for fraud motivation.
Bitcoin actually empower the price value of altcoins, it is the volume of bitcoin that mechanized the technological growth and pumping of other coins. In 2011-13 ETH was still at little price rate, but when the booming BTC price sprang forth, it empowers every other altcoin. And you can see from this period too that bitcoin is not doing well because of volume dropped from the marketcap, so it affects every other altcoins. Bitcoin can be seen as the mother coin.