The premise of trying to use metacritic to assess MMO expansions is fundamentally flawed, no matter which side of the fence you're on. MMO's are by nature a live-service style game, and expansions have a 2+ year content lifecycle that make it incredibly difficult to really rate them until they've run their course.

Expansions in 14 are particularly difficult to assess rapidly because SE basically never rolls out the new endgame systems/features of the expansion until LONG after the launch. Reviewers never even have a chance to interact with the failed systems, cut content and general patch content issues that end up being at the core of many peoples criticisms about certain expansions.

Where Stormblood was an expansion redeemed by its patches, Endwalker was an expansion undermined by them.