the problem is that he has holding next to him, who cant clean up his mistakes the way gabriel can help clean up some of tierney's mistakes. and he does not seem to have a reliable RM/RW to link up with going forward. pepe is in and out of the team, willian and him never seem on the same page.
his injuries have sapped some of his athleticism. hes not TAA or peak dani alves at this point, but hes still an average right back, and he normally always puts in a committed shift. he'd benefit from a stable formation, a more reliable CB next to him, and better attacking patterns in front of him. the technical ability is still there, imo.