Not gonna happen.
First, there’s no money for all of us to retire.
Second, in too many companies there is nobody to replace us.
As I tell my wife, “the day they put me in the pine box, I AM taking sick leave, I don’t care who it pisses-off”
“Not gonna happen.”
Lets assume that they retire because they are financially prepared to do so. They’ll all be downsizing, selling assets, equities - perhaps going into bonds and generally living off of the fruits of their labor.
The likelihood of this actually happening to financially prepared retirees advantage is probably slim.
Maybe some of them will likely retire on defined benefit pensions - and maybe they will for a while.
There are so many rosy assumptions that would have to fall into place for this to happen, it’s not even worth taking seriously.