I've had several applicants recently ask me if they need to showcase their accomplishments in their residency personal statements if they have already drafted a strong ERAS activities section. The simple answer is yes.
First, remember that you don't know at what part of your application the readers will be starting. If some start with your personal statement, and it's pale, you will have lost those readers from the beginning.
Also, note that the faculty members seeing your application are reading many more ERASes than just yours. If you only mention an important achievement once in your application, the program director might simply forget your accomplishment. After all, s/he is reading scores or even hundreds of similar applications. Your readers have to be reminded several times of your candidacy's strengths. (You'll mention those accomplishments in your interviews as well.)
To a program director who hasn't yet met you, you are what you've done. You need to use substantive examples of your achievements to demonstrate your worthiness for a potential residency position. Evidence is persuasive; use it!