Amazon & Alibaba Are The World's Most Crowded Trades

While everyone in the world appears convinced that (and positioned for) bond yields go higher, stocks go higher, gold goes lower, and risk has been vanquished, UBS notes that the world's largest, most active overweight crowded trade is in Amazon.com stock (followed cloesly by UnitedHealth.
At 175x P/E what could go wrong?
Notably, while Amazon is the most crowded long in the developed markets, Alibaba is the most over-crowded in global emerging markets...