Why does the S10+ display Looks sharper than S21U

Hi i recently upgraded from s10plus to s21 ultra i got it for 8000PHP roughly 140USD From facebook marketplace I have Tested it and though it legit because 120hz is working and the blacks are blacks when it dark but the Sharpness of the display is abit off even it is on the max resolution Model number is SM-G998U1

Is this normal