BBR was in a downtrend for so long it became far too undervalued relative to its twin XMR, and the market ran out of cheap berries.

The Supernet hype reversed that trend with a vengeance, although the steady release of improvements (miners, price chart in wallet, etc.) played a role as well.

Another factor was an uptick in XMR prices, to which BBR offers leverage as silver does to gold.

Go ahead and short BBR, you could possibly make some money in the short term.  But many of us are accumulating, and you might get your teeth broken instead.