I'm also not quite sure why "Remember the Magic" seemed to hit home more effectively than their other marketing campaigns, though building a campaign that invites people to think about when they were children or when their children were little will naturally tug at the heartstrings. It was the first massive anniversary celebration and so celebration fatigue hadn't set it. Also, for the 25th they wrapped the entire campaign around the central concept of 'remembering the magic,' whereas for the 50th they've just run a generic, somewhat unfocussed promotional campaign and slapped 50th logos onto the marketing materials.
In terms of the 50th, the issue for me with the campaigns and songs is that they could be a summer advertising campaign for WDW during any year. The Magic is Calling could have been the 2009 advertising slogan or could be the 2023 one without it fitting any more or less. You Are The Magic is also just like something that was spit out of a randomiser as the title for a new fireworks song. The nighttime spectaculars aren't designed in any way to be specific to the celebration, and the statues could, again, be an unusually uninspired promotion on an off year when they were struggling to come up with something to promote. The selection of characters and the fact there aren't even 50 statues is... weird. All you're really left with, then, are the decorations and the merchandise. Even on the decorations front, is notable that Disneyland Paris restored their castle to its original glory for their anniversary while WDW unveiled a god awful new paint scheme.
