"For years" is likely an exaggeration. The longest bear market in last 5 decades lasted just over 1.5 year. Keep in mind, share markets are nothing like they were 5 decades ago and the amount of wealth held in sharemarkets means the world would not want to see a long lasting bear market.
The last bear market lasted 33 days, the one before lasted 62 days. And the 2008 recession year bear market lasted just over a year.
