The difference is, postgraduates in academia are near the top of the food chain and provide significant value to the economy, as seen by their market rates outs

The difference is, postgraduates in academia are near the top of the food chain and provide significant value to the economy, as seen by their market rates outside academia. They are usually the cream of the crop every step of the way, and on paper they are each independently training to be at the top of the food chain once they finish. This results in a severe cognitive dissonance and isolation that don't happen in your "other job/occupation in any industry". The same is seen with medical residents, where depression is frequent. Your regular wage-slave may also feel terrible but they have already accepted their fate.