Cryptocurrencies such as Ethereum (ETH), Solana (SOL), and Cardano (ADA) have experienced a decline in their values as investors engage in profit-taking activities with Bitcoin (BTC) towards the end of the year. This situation highlights the interconnected nature of the cryptocurrency market, where movements in Bitcoin often influence the performance of alternative digital assets. As Bitcoin sees increased selling pressure due to investors realizing their gains from its recent price surge, it has caused a ripple effect, leading to a decrease in market sentiment for various altcoins like ETH, SOL, and ADA.
source: https://www.coindesk.com/markets/2025/12/15/eth-sol-ada-slide-as-bitcoin-sees-year-end-profit-taking