To be fair I probably didn't pick the best example. Blacksmiths are still needed by the very small number of well-off people who enjoy horse ownership. When you have a horse that needs shoeing, you want to hire a craftsman who was trained by their predecessors to uphold a venerable and specialized tradition, not some incompetent rando who is going to injure your horse or get themselves kicked in the head.

Then, once the job's done, you want that person off your payroll and out of your life. You don't care too much about the cost of labor, you just need it done right the first time. I can imagine a craft union being suitable for providing access to that kind of labor.

But driving cars and trucks around... yeah, no, that's a robot's job, sorry.