It’s my experience that I should over-estimate what I know otherwise I miss out on assignments that take me about 1-2 focused days of studying to get to sufficient level.

Ie I was once perfect for a project except for point 7 out of 10 which was experience with Keycloak (if you’re higher via an HR dept it’s even worse, they just tick boxes, who cares if you are smart and have broad knowledge).

So I’m now proudly Dunning-Krugering around, and use LLMs for super-charged learning. If I underestimated something I take the cost/time myself. So far it hasn’t happened to a significant degree.