According to Bobby Ong, several historical signals can suggest that the crypto bull market is nearing its peak. These include increased retail interest, such as barbers and Uber drivers discussing whether XRP or Cardano is a good buy, the rise of speculative talk about potential 100x altcoins, Coinbase reaching the #1 spot on the App Store, and celebrity involvement in cryptocurrency promotion. Traders should monitor these patterns as potential indicators for market cycle tops, which may impact short-term and long-term trading strategies for major cryptocurrencies and altcoins (source: Bobby Ong).