There is a fine line between an impressive interview and an obnoxious one; your credentials become irrelevant rather swiftly if your potential employer thinks you’re an ass.
Modesty comes at no cost, and respect is an investment which always pays dividends.
In an interview, the best chance you have at success is being the genuine best person for the job.
And when we’re not the best applicant for one role, the only sensible course of action is to become the best applicant for the next.