It's not either-or, it's all of the above. Military, commercial surveillance ("adtech"), finance, healthcare, legal, institutional administration. None of these things are entirely useless, but are still mostly zero-sum or redundant waste. Technological progress is continually making us more productive, but instead of realizing the gains (eg full time employment being under 10 hours per week by now), our economy is structured to keep creating endless make-work jobs. We're trapped in a paperclip maximizer for human labor.

Fintech pays better, but it seems like most new grads would rather go to FAANG, which in the case of GAF means adtech.

A substantial proportion of the brightest people from my generation in the UK went to work in the city of London, where they were paid handsomely for moving numbers around spreadsheets for big finance companies. What a waste.