I wish this would see wider acknowledgement.
Lump of Labor is a fallacy, people do find new jobs, and productivity does improve the economy. But none of that implies that the displaced people will be better off in the end!
Similarly, free trade agreements are economically efficient, and boost per-capita GDP. But even aside from implementation issues (i.e. agreements that go far beyond lowering tariffs), there's no particular reason that the extra money ends up benefiting the same people who get hit by outsourcing.
If anything, the studies I've seen say that being displaced by automation or outsourcing causes a permanent wage decline. The original Luddites were right - they probably saw lower wages for their entire lives thanks to automation.
Pretending that overall growth inherently means an economy which works better for the majority of people is frankly dishonest, especially (as you say) in a country so opposed to helping the displaced.
You haven't proven that. And its entirely possible that it's not worse for the economy in general, but it's quite awful for segments of it. And given the current attitude toward the safety net in the US, once those jobs are gone, that's it for those people.