You need to define what a bubble means before you can establish whether one exists. I think Uber and AirBnB suddenly going to zero would be described by many p

You need to define what a bubble means before you can establish whether one exists. I think Uber and AirBnB suddenly going to zero would be described by many people as a bubble pop and that may have dramatic effects on the sector, particularly financing going forward, regardless of its impact on the broader economy.