Millenial engineers tech gods say PET Trump can't bring back jobs because the robots will and have taken them. Like, totally true?

Aye, indeed I am a believer. Many jobs are gone forever as long as there is technology to replace them.

It is true and it's the nature of the beast.  
Some people are going to be really pissed off in 2-3 years when those promised jobs don't materialize

Yes, as I've noted many times in this forum.

I cite the example of car manufacturing, which was considered the prototypical path for low-education workers in the USA to join the middle class.

In the 1950s, the Detroit-based Big 3 needed 50-60 man-hours to build a car.

In the 2010s, car makers worldwide need about 10-15 man-hours to build a car (high-end boutique manufacturers like Aston-Martin excepted).

The 3 out of 4 car manufacturing jobs which ***used to*** exist were not sent, in general, sent to China or Mexico (although some were). They were eliminated by manufacturing efficiency and robotics.

The same principle applies in occupational domains across the spectrum.

But people want to believe in the fantasy that hard work = success, so they refuse to grasp the concept of human labor obsolesence.

Totally.  I love your PET Trump. That is his new title.

3D printers.  Everyone is an inventor now because of a prototyping tool.  Go invent some POS  bottle opener that has a Linux Tux logo and fits in a duck tape wallet.   Yay progress!