Will so many people switch to plumbing though ? Really depends on how old you are when you get canned (I don't think its realistic for most 40 year olds to start a plumbing career), how good you are with your hands and physical things and whether you can survive the switch psychologically; I don't see many investment bankers or software devs survive such a switch. I'm 42, even if I was very good with my hands (which I'm not) I don't think it would have been a realistic transition; by realistic I mean survivable psychologically.

So people will not all switch to plumbing, indeed. But then to what? There's only so much need for tattoo artists and geriatric care - which your customers must also afford to pay.