In finances history may not repeat itself. Investors always say past events can't be used to foresee future events. Last time bear market lasted 3 years, but this time it can last less or more, although due to bitcoin's popularity and demand it's probably going to last much less than 3 years. Many people think like you, so they will wait 3 years to enter the market again, as it worked like a cake's recipe.
Meanwhile, clever investors, who are already aware about the common general mindset will enter the market before 3 years, suddenly pumping bitcoin and finishing bear market. So those who will be still waiting are going to be taken by surprise and everyone around will hear that fateful phrase again: *I wish I had bought bitcoin before...*