Interesting (and disturbingly true) read.
One thing that many seem to miss is that off-shoring jobs is literally the tip of the iceberg. Automation is responsible for 90% of jobs lost in the US over the past decades. That's why reshoring, while helpful, won't solve the problem.
It used to be that you could get a good salary for turning a wrench at an automotive factory. Now, the wrenches are turned by robotic assembly machines, and far fewer actual humans are needed to program and maintain those machines.
However, that being the case, there's still the undeniable truth that tax cuts over the decades have disproportionately helped the ultra-wealthy.
You said, "Put simply: trickle-down economics didn’t." Perhaps it would be more accurate to say that benefits did *trickle* down, but the overwhelming majority of benefits were retained at the top. If you increase by $50k the income of someone making $50k, they'll spend most or all of it. If you give that same increase (let alone one of $500k) to someone making $500k, they'll invest almost all of it.