previously Altcoin can do that without following the bitcoin price movements, I remember when in 2015-2017 Altcoin movements were very fast. almost every Altcoin can produce even though BItcoin is not moving (stable). And it is very profitable for day traders. but the current pattern has changed. where Altcoin really follows BItcoin prices. and for now, it might continue to follow the price movements of Bitcoin I guess
Maybe last 2015 until 2017 altcoin can do it alone without allowing procedure from bitcoin with higher price and altcoin keep going to higher price, but last 2018 and 2019 altcoin always allowing how bitcoin price and situation, if bitcoin keep lower price altcoin without ask anything keep stable with lower price and only raise up after seeing bitcoin have on the top price.