I think the fear comes from the span of time. If my job is obsolete at the same time as everybody else's, I wouldn't care. I mean, sure, the world is in for a very tough time, but I would be in good company.
The really bad situation is if my entire skill set is made obsolete while the rest of the world keeps going for a decade or two. Or maybe longer, who knows.
I realize I'm coming across quite selfish, but it's just a feeling.
If AI truly overtakes knowledge work there’s not much we could reasonably do to prepare for it.
If AI never gets there though, then you saved yourself the trouble of stressing about it. So sure, relax, it’s just the second coming of GeoCities.