Stacks (STX) copies Bitcoin price movement: what's the relation?

Today’s Stacks price surge has outperformed most altcoins. It was ranked at position four by CoinMarketCap among today’s top gainers behind Render Token (RNDR), Conflux (CFX), and Injective (INJ), in that order. STX price seems to mirror Bitcoin price which just surged above $30,000 earlier today.