You're not going to automate a plumber, but we can design plumbing systems which are less likely to have issues and/or are easier to repair for non-specialists,

You're not going to automate a plumber, but we can design plumbing systems which are less likely to have issues and/or are easier to repair for non-specialists, and thus reduce the demand for plumbers. You'll still need some for the exceptional cases, of course. Not that I disagree with the core point: There are jobs which are both necessary and very unlikely to be automated any time soon.