SingularityHub quotes a study that asserts half of jobs could be automated and/or replaced by computers. I think “Half” is probably hyperbolic in the short run (depending on how much improvement you assume in both hardware and software.) However, the core concern is legitimate.
The one that I’m most concerned about in the next decade or two is truck drivers. It’s a huge number of jobs that will most likely disappear almost overnight with the advent of autonomous vehicles. Anyone doing cross-country trucking ought to be assuming retirement in the next 10-15 years or so– and either saving or retraining with that in mind.