It's also the distorted ability to rack up ungodly amounts of debt without facing the normal consequences of doing that. The US economy is booming, but it's borrowing from two decades from now to fuel the moment. When their debt gets unmanageable, the world's economy will enter a depression, IMO.
Maybe, but low interest rates have been over for two years and so far, so good.
Also, not exactly borrowing from the future (this is impossible without a time machine). More like borrowing from others based on expectations about future income.