This new emerging phenomenon has something to do with people realizing that there's no intrinsic value in "things" ( i.e. houses/cars/that new set of golf clubs etc.), and choose to lead the things-free life, being ready to move to new, better and bigger... not things, but opportunities unencumbered by huge mortgages and deep entrenchment in your particular place of work or residence. This emerging class of people believe in liquidity of their life and money.
And (I would add ) it would be increasingly difficult to sell these people the good old Wall St. notion of giving someone all of their actual hard-earned "retirement" money for 30 years for the promise to be "prepared" for the old age.
Most doctors I know are far from any kind of unconventional thinking, so I won't expect this idea to grasp most of us any time soon.
Time will tell..
Will be happy to know your thoughts on that.