Air B-n-B and Uber followed a "rental" model that has predictable effects, and whether you consider them negative is a matter of perspective. When you take assets that are underutilized by their owners, and shift to a rental model to allow more efficient utilization of said assets, you increase the value of those assets tremendously, and effectively increase collective wealth.
To the extent it gets ugly, it's when you start maximizing how much value you extract out of the model. If you extract nearly all the value you've added, then the net benefit for everyone else is pretty minimal. This is where competition is supposed to step in to balance things out...
Air B-n-B and Uber followed a "rental" model that has predictable effects, and whether you consider them negative is a matter of perspective. When you take assets that are underutilized by their owners, and shift to a rental model to allow more efficient utilization of said assets, you increase the value of those assets tremendously, and effectively increase collective wealth.
To the extent it gets ugly, it's when you start maximizing how much value you extract out of the model. If you extract nearly all the value you've added, then the net benefit for everyone else is pretty minimal. This is where competition is supposed to step in to balance things out...