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So it's still considered "first person" by most, but the pronoun is dropped.
Can I be sure that no using "I" on resumes is a "big component" for my success? Of course I can't be 100% sure, and my ability to highlight accomplishments is probably far more important.
But I was a recruiter for 20 years, and I know that 95% of resumes I saw during my career (easily in the tens of thousands) were written in implied first person, and when you send someone a resume that continuously uses "I" it is a bit of a shock to the system (just as it would be to see third person).
I'll tell you what, let's save us both some time. Go to Google and just search "resume", and use image search. I just went through the first page of results, and I didn't see a single resume written in first person (using "I"). Not one.