QDM, QDR, QTE & QUJ, are archaic British codes for things that no one in aviation ever worries about anymore. Its easier to say what you want.
I'd agree with you with one exception.
Several odd years ago I was going through the recruitment process for an operator in Africa. An exam was provided to candidates that was fairly basic....until it asked me about Q codes. Not having ever even seen them before I guessed (multi choice) but did not do well.
Long story short I did get the job but afterwards there was a discussion as to how I had an Instrument rating and yet had no idea about Q codes. Simply not covered in our syllabus. Fast forward nearly a decade and various jobs later and I still have no idea which Q code is which!