How to decide whether I should use “we” in an essay?
You're doing a postgraduate degree, so you should have been taught / be about to be taught the basics of academic writing.

Here is one of the basic rules.


Follow the style guide.


You've been told what the style guide for your coursework says about personal pronouns: it says don't use them. Follow it. Don't use personal pronouns in your coursework.

When you write for something with a different style guide, follow that style guide instead.

Different style guides have different rules. That's what makes them different.

No, it is not ostensibly silly to have different writing styles from the same person, assuming that person can comprehend and follow Rule 1, above.