That certainly seems to be the direction we're heading in, especially if Disney is not going to be able to court new corporate sponsors to update Future World.
Honestly, I'm really surprised they have been able to retain any. If you notice, the majority that are left have some other business relationship with Disney and this is just a part of it.
When you think about it, the notion is completely absurd. Why in heck does a major corporation with record profits like Disney need someone to sponsor their rides. This ain't the World's Fair, LOL.
In the early days it was easy because Epcot had cache, it was seen as prestigious and forward-looking to be a part of. As we know, those days have long, long since passed.
I'm also sure that the companies involved don't really end up with much benefit over it, either - I mean, dumb as folks are, will they really change their preferred brand or model of a major purchase like a $20,000++ vehicle because of Test Track? (I always laugh because it seemingly breaks down so often when I'm in line - what stellar advertising!) Are you going to stop drinking Pepsi when you get home just because Disney only allows Coke (if anything, it makes me appreciate Pepsi all the more, as a Diet Pepsi drinker). Are you going to stop buying your preferred brand of film...oh wait a minute, no one buys film anymore, well, in any case, you get my drift.
It's like when billionaires run for office and then beg for donations...if you don't believe in your campaign enough to pay for it, I'm sure as heck not going to give you $100 of my money when you can afford to wipe your behind with it.
Disney doesn't reinvest in Future World because it serves it's purpose - it is just enough to get folks to see value in spending part of a day there since they paid for their pass anyway. It also gives folks something to do on their way to or from the epic-sized shopping mall/food court on the other side, where they make their real money on merchandise and food, that ranges from overpriced-even-for-Disney to obscenely almost criminally overpriced. Oh, and of course the biggest profit in all of Epcot - and probably WDW - on alcohol, which as anyone can tell you is what keeps most food establishments who serve it in business anywhere, much less a relatively dry place like WDW.