The cryptocurrency market has seen remarkable cycles over the years, with the 2017-2018 altcoin season often regarded as an unparalleled 'S-tier' event by traders and analysts. A recent tweet by prominent crypto influencer Pentoshi, posted on May 30, 2025, reignited discussions about the historic altcoin rallies of that period, describing them as 'insane times' with gains as high as 200% on certain projects. This era was marked by explosive growth in altcoins like Ethereum (ETH), Ripple (XRP), and Litecoin (LTC), fueled by retail investor frenzy and the ICO boom. For context, Bitcoin (BTC) surged from around $1,000 in January 2017 to a peak of $19,783 on December 17, 2017, as reported by historical data from CoinMarketCap. Altcoins followed suit, with ETH climbing from $8.17 on January 1, 2017, to $1,432 by January 13, 2018, a staggering 17,000% increase. Trading volumes during this period were unprecedented, with daily volumes on exchanges like Binance and Bitfinex often exceeding $10 billion by late 2017, reflecting massive retail participation. The stock market during this time was also in a bullish phase, with the S&P 500 gaining 19.4% in 2017, per data from Yahoo Finance, creating a risk-on environment that spilled over into crypto markets. This correlation between traditional markets and crypto was evident as speculative capital flowed freely into high-risk assets like altcoins.

Fast forward to the 2020-2021 cycle, which Pentoshi ranks as 'A-tier' or potentially 'S-tier,' driven by unique macroeconomic conditions. The COVID-19 stimulus packages, coupled with global lockdowns, created a perfect storm for crypto adoption. As Pentoshi noted, with people confined to their homes and stimulus checks in hand, trading became a popular pastime. Bitcoin soared from a low of $3,867 on March 13, 2020, to an all-time high of $69,000 on November 10, 2021, according to CoinGecko data. Altcoins like Cardano (ADA) and Solana (SOL) also posted massive gains, with ADA rising from $0.03 on March 13, 2020, to $3.09 on September 2, 2021, and SOL jumping from $0.51 on March 16, 2020, to $259.96 on November 6, 2021. Trading volumes spiked, with Binance reporting daily volumes surpassing $80 billion during peak euphoria in November 2021. From a stock market perspective, the S&P 500 rallied 67.7% from its March 23, 2020, low to December 31, 2021, fueled by Federal Reserve liquidity injections, as per Bloomberg data. This liquidity also boosted crypto, with institutional money flowing into Bitcoin ETFs and crypto-related stocks like Coinbase (COIN), which saw its stock price rise from $328 on its IPO date of April 14, 2021, to $429 on November 9, 2021. The cross-market correlation was clear: as stock market risk appetite grew, so did speculative investments in crypto, creating trading opportunities in pairs like BTC/USD and ETH/BTC.

From a technical perspective, both cycles displayed classic bullish indicators before their peaks. In 2017, Bitcoin’s Relative Strength Index (RSI) on the daily chart hit overbought levels above 80 by December 7, 2017, signaling a potential reversal, which occurred shortly after. On-chain data from Glassnode showed BTC transactions peaking at over 400,000 daily by December 2017, reflecting retail FOMO. In 2021, similar patterns emerged, with BTC’s RSI reaching 89 on November 9, 2021, and on-chain active addresses hitting 1.2 million on November 10, 2021, per Glassnode metrics. Altcoin trading pairs like ETH/BTC also showed strength, with ETH/BTC peaking at 0.082 on December 7, 2017, and 0.085 on November 9, 2021. Stock market correlations were evident in both cycles, as the S&P 500’s Volatility Index (VIX) dropped to lows of 9.14 on November 3, 2017, and 16.26 on November 5, 2021, indicating low fear and high risk appetite, per CBOE data. Institutional involvement grew in 2021, with Bitcoin futures open interest on CME reaching $5.2 billion by November 9, 2021, signaling significant traditional finance inflow. For traders, these cycles highlight opportunities in altcoin rotations during risk-on periods and the importance of monitoring stock market sentiment via indices like the S&P 500 for crypto market timing. Understanding these cross-market dynamics remains crucial for navigating future cycles and capitalizing on volatility.