My son is in the 3rd year of apprenticeship, so closing in on journeyman. These will be growth jobs for now, but those openings are not nearly enough for all the workers being displaced even if they have the required intelligence and skills.
You have to remember half the population is below average intelligence by definition. The intelligence required to be a warehouse picker is significantly lower than to be a skilled mechanic or diagnose electrical faults. That's not to say warehouse pickers are stupid, some will exceed the minimum to do the job of course, but even if there were unlimited trades jobs many just wouldn't be able to learn to do it. IQ is largely immutable, someone with an 85 IQ can't just work harder or study more to get to a 115 IQ any more than someone who's 5'4" can work their way to being 6'1".
The industrial revolution was so successful in job creation because the industrial jobs it created were an easy transition for agricultural laborers. If you could harvest crops, you could put wheels on a Model T. The same is not true for the Information Revolution, and AI hybridized with talented humans working in tandem is stretching that gap even more.
In real short terms: You can't have a robust middle class without jobs for the middle IQ bands that pay wages significant enough for economic and social mobility for both the worker and their offspring.