Bitcoin's price has retreated to $87,871 after briefly reaching $90,000 on December 29, 2025. Analysts warn that failing to sustain above $90,000 could lead to a pullback similar to 2019. Bitwise CIO Matt Hougan suggests the traditional four-year cycle is giving way to a ten-year gradual rise. Meanwhile, Solana (SOL) is trading near $125.85, marking a decline of over 12% from its monthly high. Solana's DeFi total value locked (TVL) has decreased to $23.8 billion, and ETF inflows have dropped to $13.1 million last week, highlighting the importance of maintaining the $120 support level.