The one thing that holds me back from really liking this is that skills have to be rated out of 5, which I believe is entirely arbitrary. Especially for someone like me, a maths student.

How good is my Python out of 5? In what areas? Compared to who, someone with 30 years of Python experience or my peers who've never coded before?

Furthermore, with natural languages, there are commonly used scores (CEFR in Europe at least) that are more or less objective and don't depend person to person. If someone says they're B1, you know what to expect. If someone says they're 3/5, what does that mean?

I would like the option to not justify how skilled I am at something, or have more flexibility to qualify/quantify my skills such as, but not limited to, number of years of professional use.