You can say that thesis has been disproved by Spravato. There are ways to commercialize and even prescribe off-label. I've been taking prescribed off-label ketamine for 4 years.

you just need time and lobbying, canada partially legalized some psychedelics, even some US cities

just like with weed it's going to take a good while

also we didn't try to push spice/K2(thc analogs) for PTSD, anxiety or insomnia AFAIK, because we're well aware that using analogs is usually really dangerous

and MAPS.org seems to do pretty well, with enough groundbreaking studies I'm sure legalization will come, in time