Power creep is SE's game plan.
There's a difference between power creep that occurs as a part of natural progression and that which occurs from balancing. Only former is intentional (And let's face facts- Even with audolin, FFXI has considerably less of a power creep issue compared to typical MMOs which alluse straight up linear progression. What we have in XI is sort of a hybrid- But even then, item levels in XI are meant to approximate real ones, and the highest ilvl has held steady for quite some time). I don't mind vertical progression much only because it usually means less inventory stress and fewer items needed to complete a kit- but loot is more interesting and fun overall in XI's approach)