I don't understand this reasoning at all. From a business standpoint, if Disney had made decisions in earlier years as they do today, they would not be enjoying anywhere near the success that they enjoy today. Disneyland, if they had the stones to even consider making the investment, would have been one giant Fantasyland. No tributes to the Old West, no visions of Tomorrow.
Mansion, Pirates, Space Mountain, The Matterhorn, The Monorail, Epcot, even Animal Kingdom, ... would never happen.
Sure, it's easier to connect the dots when you are "leveraging your IP to capitalize on profitable franchises". But in the big picture, that's extremely low risk, low reward, AND it is very limiting. It takes homeruns like Mansion, Pirates and the Monorail completely off the table. It cripples your ability to reach new audiences, to expand your markets. It constricts the company's creativity to the studios division. It turns the parks into a marketing arm, rather than allowing it to be it's own cauldron of creativity.
They aren't practicing "good" business. They are practicing easy business.
(mandstaft, I do not mean to single you out on this, I've read comments like yours over and over to justify decision after decision, year after year. Your comment just happens to be the one I hit reply to today.)
While I can't speculate on what would or would not have happened, I do agree that from a long-term perspective, Disney does not stand to gain very much from basically playing catch up with Universal.
One can make the argument that the original themed lands of Disneyland/Magic Kingdom may be outdated: Adventureland was shaped by old pulp novels and the annexation of Hawaii/co-opting of Polynesian culture, Frontierland was a product of the 50s and early TV's focus on the myths of the Old West, Main Street USA meant a lot more to grandparents in the 50s who may have actually lived through the turn of the century, and Tomorrowland was an extension of 50s/60s Cold War investments in STEM fields and Space Race excitement. Pointing any of that out is absolutely fair.
However, there's no getting around that the sheer concepts of "adventure", "frontiers", "tomorrow", and the very concept of nostalgia itself are great levelers that can make a land or attraction very appealing to people of all ages; they're archetypes, so they tend to resonate with wide swaths of the population, and they're fungible enough that over time you can fine tune the concepts as tastes and cultural influences evolve.
In this way, Disneyland and WDW became places that held great allure for people of all ages (even putting aside for the moment the other additions at various resorts that made WDW so attractive to older tourists in the "Vacation Kingdom" days), and made lifelong fans out of multiple generations of park-goers.
A shift toward "market the hot IP" is inherently limiting, even if the IP being utilized is very popular. Some IPs are exceptions: Potter, for example, and I believe that Star Wars can be, but most are transient by nature, and they come with the immediate caveat of "you may not enjoy this as much if you're not familiar with the IP in question". Cars Land avoids this by blending into California Adventure with the concept of riding Route 66, the road trip concept being so familiar to so many people in North America, but it's something that MUST be considered and done very carefully lest the area date itself before a decade has even passed.
Said it in another thread, but such a strategy risks a drop in longterm, lifelong fans due to the limiting nature of IPs that require some familiarity with the source material to be optimally enjoyable. Disney may not really care about that: maybe they're happy if people in the parks are just getting the message "keep seeing our movies and buying our stuff". But I fear that will lead to less interest in general in the parks, less committed fandom, and thus a reduced source of customer loyalty to the Disney brand, which, let's face is, is a
gigantic factor in Disney's theme park popularity.
One day I may have children, and I'm ready for when those kids will want to watch the same movies and listen to the same albums over and over again. If I bring those kids to Disney World, though...do I really want to spend thousands of dollars just so we can hear the same songs and see the same scenes repeated to us again? Or would I be more likely to bring the kids annually (thus creating new lifelong fans) if we knew there was a lot of stuff down there we couldn't see anywhere else?