If you expected to learn useful finance at a university, you already failed as soon as you applied. If anyone there knew what they were doing financially, they wouldnt be there, and especially not teaching Finance 102. In case you were not aware, nearly all professors hate teaching lower level classes, so they naturally get forced on the worst performing professors (the ones that are closest to getting fired).
Concluding that the entirety of TA can not be useful (the Null hypothesis is true for all input signals) just from seeing that a few strawman TA in finance 102 not work is beyond absurd.