''previous bear markets'' there was really only 1 previous bear market, bitcoin is too new to look at the past. The space is way too different now than it was back then, more coins, more volume, more exchanges, better exchanges, potential good news, etc etc. There is no reason to think this bear trend will continue for 2 years.
were you around in 2014? "but there's so much good news! this space is nothing like it was in 2011!" new exchanges were launching and the chinese exchanges were flourishing. new merchants were coming online. crowdsales like mastercoin and ethereum were sucking up coin supply. and yet price kept falling.
there were also bear markets in the second half of 2011 and 2012, and also in mid-2013. the bear market you're thinking of was just the longest one, the only multi-year bear market. in my observation, the market moves much slower (in both directions) as time goes on, particularly after 2013. the post-bubble bear markets are likely to be more prolonged now as a result. i'd be happy to be proven wrong on this, but there's not much to go on
besides historical price action and cycle analysis.