If you are interested in investing in government bonds, macroeconomic forecasting could be quite important, but overall, it doesn't help you much for stock return predictions. In fact, very few variables (macroeconomic indicators included) show robust power to predict market returns.
If you are in social science/humanities, usually students are not paid by professors' grants. Thus professors do not push students. That being said, it'd be very difficult to get good advising if students do not show effort. In natural science/engineering, it's a different story as advisors usually pay phd stipends out of their own funding and thus expect them to be competent RA/TAs.
