Walt Disney, after he had announced the WDW project and before he died, was quoted as saying that he wanted to offer accommodations in Florida from tent sites to hotel suites (or words to that effect). That's why Fort Wilderness is one of the original resorts from 1971 and currently being celebrated during the 50th anniversary celebration. The builders of the MK leading up to 1971 included the Fort (loops 100-600 and the Settlement Trading Post mostly) because they wanted to stay true to Walt's dream for Florida.
The use of the land for generating Fort revenue is not as profitable as it is for the hotels in absolute terms but this isn't
Disneyland where vacant land became non-existant. WDW has lots of land available for more vertical resorts so the Fort chugs along.
I've been to Disneyland Paris and noticed that there is a Disney resort named "Disney Davy Crockett Ranch" at DLP (although located slightly away from the other Disney resorts there) and it is basically the Fort minus campsites. In other words - only "cabins" which are higher revenue producers. Disney (or their investors/partners) don't offer campsites anywhere else that I'm aware of as one of their own resorts.
DLP's Disney Davy Crockett Ranch
Oh I noticed no Disney transportation is offered between DCR and the DLP parks. You gotta drive.
We are lucky to get the campsites we have even if they'll never be expanded (although, hey, we did get 2100 converted back to a camping loop and away from being a cabin loop) but the economics are always under review I bet.
I remember when I went to Disneyland back in the 90s there was an RV park (not operated by Disney) on land off the northwest corner of the original MK. You can see the angled parking of the trailers (pull through I guess) in the upper left. Now that land has a Disney parking deck on it.
Image date is October 1995. Dreamed about staying there (didn't have a camper/rv yet) but knew I wanted to some day.
So for the OP, I don't know that Disney "regrets" having the Fort. It's there and it's a cash cow so they keep it operating. If/when land becomes scarce, that's when we start losing stuff.
Bama Ed
PS - And I suggest that the Fort isn't the cheapest resort because it might have the lowest operating expenses. Disney doesn't use cost-plus pricing for sites and cabins. They manage their expenses to maintain and service the the Fort at the desired levels. Then they charge AS MUCH as they think they can to maximize revenue. As long as revenue > expense,