Before any bubble phase begins you need two things to happen. First you need the central bank to make a policy mistake and create too much money and keep interest rates too low too long. Second you need a big corrective move to stretch the rubber band far in the wrong direction and get everyone bearish. This is the fuel to drive the bubble phase.
Folks try to use some common sense. We have negative interest in most of the world and have had ultra low interest rates for 6 years. Every central bank in the world is printing money and intervening in markets. This is not the recipe for a deflationary bear market. This is the recipe to produce another bubble phase.