There are some platforms and services that are now offering crypto portfolio grading as a way to evaluate the performance of a portfolio. However, I have several friends (investors) who argue that its useless.
I was wondering if anyone here has used it? If so, did you find it helpful in making investment decisions? What criteria did it use or should use to grade

It is good. So you can track the progress or the history of the portfolio. Also, you can brainstorm with some other person to get his feedback. This will improve your technique or skills.