Inevitably, the altcoin price will accompany the increase in Bitcoin prices because it refers to USD, but it will be different if the altcoin price refers to the price of Bitcoin because it tends to fall. That in my opinion, but not all altcoins have decreased from the price of bitcoin.
Altcoin follows bitcoin in trading, meaning that when the bitcoin price rises most of the altcoins also rise, when the price of bitcoin goes down the effect is also the same. In general, investors buy altcoins for bitcoin assistance, or they invest altcoin when bitcoin falls.
The altcoin's growth was triggered by the increase in bitcoin so that all trades were crowded because investors wanted to diversify their capital to avoid risk, or to increase profits.