Does it though? The majority of the original attractions in Epcot focused on the history of certain subjects with the futuristic portions either being vague enough to be adjustable and updatable, or were quite fantastical as with Horizons. I think that the idea of "outdated Epcot" is a myth because Eisner wanted an excuse to build cheaper and more thrilling attractions to encourage corporate sponsors to renew.
Good point, and yeah, it was likely the heart of why so many classic EPCOT rides focused on the past for awhile, since updating to reflect new historical studies would always be simpler than having to update to suit the "new future".
EPCOT did suffer from being built just as the era of "the great big beautiful tomorrow" was ending; America had basically convinced itself in the post-WW2 era that we were mere decades away from Jetsons-style living (I exaggerate slightly for effect), but a whole host of issues that this isn't the venue for diving into happened that made a lot of that moot. Fair point, and definitely something that EPCOT would have to adjust to!
However, the concepts of communications, of ecology, of energy production, of transportation, etc.? Those have
never gone away. We've changed how we talk about them, sure, but there's still an endless array of incredibly exciting concepts out there that, no, we likely can't approach with that "Golly gee, Mr. Wizard, early post-industrial America can sure do anything!" air anymore, but there's still a million different things to explore and ask questions about that could keep them totally relevant.
Basically, maintain the timeless aspects of rides and attractions (e.g. the bulk of Spaceship Earth), but tweak the endings as needed or build up more interactive spaces for people to get a hands-on look at some of the newest ideas...not Innoventions style, as large tech companies are loathe to share prototypes with the public (and their competitors), but why not talk about ideas going on around the world today for improved, say, high speed transit? Alternative energy? Advanced food production? Preserving the oceans? That's not that hard to update, and it's not like people (and children!) don't enjoy visiting things like science museums and other more educational destinations. And heck, if the goal is timelessness,
then don't destroy timeless attractions like the original Journey Into Imagination!
But yeah, I said this in the Harmonious thread, but I think for a lot of us we know full well that EPCOT's been suffering for decades now, but as long as the "skeleton" of EPCOT Center remained there was still that hope that things could be righted, and there were still aspects of the original park that remained that could remind you of why you fell in love with the place originally. Seeing those parts get gutted and the replacements fail to inspire makes it easy to feel deflated in spite of the new investments.