How you describe yourself is one aspect of Dunning-Kruger: highly competent people often do not think that what they do is anything special, even though in reality, their skills are very rare and highly sought-after.
Yes, but the inverse is not true. There are plenty of incompetent people who probably also think that they're incompetent. Thinking you're incompetent does not imply that you are competent.
How you describe yourself is one aspect of Dunning-Kruger: highly competent people often do not think that what they do is anything special, even though in reality, their skills are very rare and highly sought-after.