The reality is if you don’t compete required work/pass required tests, it’s only expected that you won’t pass a class. That’s just how it goes. It’s no matter how you feel about the course or professor or education or ethics, if you don’t meet requirements you don’t get a credit.

It’s the same with employment, if you don’t do your job you don’t get paid and eventually you get fired. It doesn’t matter that you dislike your job or think task assigned to you is stupid, if you don’t do your job you don’t get paid and you don’t get to keep the job.

It’s quite simple. And I think dean was clear: whatever you wrote in your portfolio was interesting but you haven’t met class requirements

To answer your last question, it’s possible that you aren’t getting a degree because you aren’t completing course requirements