Disagree. Sure he gets mugged by elemental yonko commanders but he for sure beats the strong men of yonko crews like Queen, Jinbei Jozu etc. His fruit doesn't have upper limits and he is already a competent combatant in terms of speed and haki and technique. The fruit for sure places him as a high tier.
what feats has Burgess shown that he can compete with Y1/2
He literally got negged by a YC1/2.
what speed feats what haki feats what technique?
"high tier" lower end if even that