Well, where QM really comes into play the most is probably in the chip fabrication industry, all the nanometer-scale processes involve rely heavily on that theory. If you get an applied physics / quantum mechanics PhD from a leading research university today you can get a very well paid job designing and troubleshooting the machines that go into a chip fabrication setup.

Claiming it wouldn't be possible with JvN is a bit much, though. It was Heisenberg who developed matrix mechanics the most, along with people like PAM Dirac. JvN put the mathematics on a firmer footing, but claiming he should be viewed like Einstein, it's kind of silly: https://en.wikipedia.org/wiki/Matrix_mechanics