Sounds like your priorities are right where they should be
Although I notice a disturbing omission from that list... if you're from the UK, you do realise it's your moral obligation to visit DLP as much as possible, right? ;-)
More seriously - I suspect WDW really depends on the 3-week on-siters... Even if they stray to Uni for a day or two, they'll be spending most of their time at WDW, and even if they spend less per-day than a 3-day guest, the total spend is pretty huge.
Just as an example, that day hitting the shops in O-Town's malls is going to look a lot less attractive if the prices are higher than back home... And the extra per-diem cost will reduce the justification for longer trips.
I guess there'll be a delayed effect since most bookings are done way in advance... But they must be concerned by the fact they're selectively discouraging their most profitable guests from visiting.
Actually... I was in DLP 8 days ago!
(Currently in the middle of writing a Trip Report in the Trip Reports section!). I've been there many times... but mostly in the 90's. It did seem special then and I used to love visiting. I've only been twice in the last 10 years, 2011 and then last week. And I have to say though, even with re-investment (and I know there is a lot ongoing now, as well as more to come) that it still is in pretty rough shape- we just spent a day there, but it was enough for the time being. A lot of the problems that people people complain about here regarding WDW are a lot worse in DLP- maintenance, cleanliness, customer service, expense... we're not really inclined to go back for quite a long time.
Whereas, we still find a lot of value in Orlando, which is why we still spend 2-3 weeks there. Not all onsite, but often at least half the time. They're not discouraging us yet... so that's where I will disagree with you. Maybe if we only went to Disney and exclusively Disney for all our holidays it might decrease in value and appeal to us, I don't know. I honestly haven't noticed a huge bump-up in prices in our on-site stays in the last 5 years. So for now we're still happy to visit!
When in DLP I kept thinking- now I can see chipped paint, faded buildings, holes in the pavement, filthy restrooms, rude CM's, litter, a lack of atmosphere, QS meals that were 3x the price of those in the US parks... And this is what is described of WDW, yet when I'm at WDW myself, I honestly do not see most if not all of the main complaints. I can see them in DLP so I'm not a crazy brand addict... so I don't know.
I also don't think the other people who book far out and come once every few years for weeks at a time will stop coming for a while yet... I think Disney is already seen/presumed as expensive and the "big trip". And when you visit infrequently it's still "fresh" because it's been a while since you've visited, so you're ready to do the "same things" again, as well as the few newer experiences. There's a lot to be said for the "American experience" element when visiting Orlando from abroad also... which personally adds to the experience for me and other people I know who visit.
The dollar has fallen recently but not enough for prices to be higher than back home... I'm not sure that will happen really... Everything always appears cheaper! It may become similar in price perhaps, I don't think that prices will ever be more expensive than in the UK! Well, except for UK products in the US supermarkets! HOW much for a tin of baked beans and a jar of Marmite?!
Edited to add: I guess I'm more of a grey area person- I don't see why everything has to be "Disney is awesome" vs "Disney is rubbish- look at all the other places you could go instead! Why would anyone go or waste their money?!" instead of "There's lots of great things and places to see all over... you could go to this state which is great, or this country which is great, or experience this unique thing over here... or, if you're looking for a theme park holiday, Disney/Orlando is a great place to go."
Disney is still far ahead of a lot of theme park resort destinations (not getting into a Uni vs Disney debate, I like and enjoy both tremendously). For example, as I have recently seen- Disneyland Paris. WDW is miles ahead. And so if a theme park resort holiday is what you're wanting to go for, then Orlando is the place to visit. If it's not, then go somewhere else, of course! Or, like we do... do both.