If you notice, a lot of these people in that article are in hardware design: electrical engineering, probably Verilog and the like. A lot of that work has successfully been outsourced which I think is the real cause of the decline. I suspect it didn't look like it was a particularly bad field to be in until it suddenly wasn't.
It's a long way from webdev though. And yeah these are presumably smart guys who could pick up webdev, but could they make the career transition without getting bumped back down to Junior by the hiring manager? And who wants to hire a 45 year old junior web developer?
There was an article recently about YCombinator shifting its investments to biotech. Suppose webdev dried up and all the funding started flowing to biotech. I'm sure I could learn what I'd need to know and I bet you could too, but could we head over to the biotech companies and sell ourselves as "middle aged web guys, self taught biotech engineers (no experience)?"