Using a graph that shows soaring productivity to argue that soaring productivity isn't happening seems a little counterintuitive to me. But I'm not a prize-winning economist, so perhaps I'm missing something.
The US economy can't be fixed by educating more plumbers. The core problem is that the US has turned itself into a peacetime rationing economy. Essential services - healthcare, education, housing, financial support - are strictly rationed for reasons that are strictly unnecessary and economically destructive for the majority of the population.
The extracted value paid by individuals to the companies that provide and finance these services is effectively a privatised form of tax. It's vastly more onerous than the official tax rate, while providing no true public benefit - and no democratic representation.
More plumbers and electricians won't change this, because they'll still be working in a system where they'll have to charge unaffordably high prices to make a decent personal profit after the "corporate taxes" on health care and education (and personal housing) are paid.
Ultimately it's a political choice to run a starvation economy for most workers, and that won't change unless there's a political shift.
Which badly needs to happen. This is not about automation, and it's not about AI. There's a huge amount of productive work that isn't being done - new infrastructure, maintenance of old infrastructure, childcare, health care, education at all levels, housing, trade and building work, academic research and open-ended no-immediate-return blue sky R&D - because the political economy is biased against that kind of activity rather than for it.