Disney screwed up that Galaxy Edge thing from what I hear, they went mostly in on the sequel trilogy, when tons of hardcore hate those movies, instead if the OG series, and they set it right at a preexiting theme park, so it was competing with itself. A new cool location would have been better like Universals new smaller theme parks, like the horror one they are setting up in Las Vegas.
I mean, I don't think they were "competing with themself" at Disneyland, they were just driving more traffic to Disneyland. The situation in Orlando is a little more complicated, because they put it at a less popular park in a multipark resort. Fundamentally I think the real problem is that there is significant lead times on these major attractions, and Galaxy's Edge was being developed from the time they bought Lucasfilm, and maybe it would have done the sort of numbers that they were looking for if it had opened as Disney's first Star Wars foray, or even after
The Force Awakens (which, despite grumbling from certain grumblers, mostly left the public still in the "take my money" mood they are after a long dearth of no Star Wars). But then Disney went full saturation Star Wars with a movie coming out every year, and then TV shows, and even big fans wanting their Star Wars fix, felt reasonably satiated without making a trip to a damned theme park. So Galaxy's Edge has been visited by everyone who would normally go to a Disney park, by some super fans, and by less committed fans in areas where its a day-trip, but it hasn't been making the sort of numbers of people plan trips to Disney parks who wouldn't that it might have if Disney wasn't exploiting that IP to death in every other way. Yes, better movie outings might keep the fan base more ready to spend by a degree, maybe the park could be better, etc., but fundamentally there were only ever going to be so many Star Wars dollars to be had each year, and Disney has tried to grab them in too many directions at once.
A similar phenomenon happened in the early 00's of there being so much Star Wars merchandise that the hardcore Star Wars collectors stopped collecting. Which, tangentally related to D&D, had to do with Hasbro overpaying Lucas for the toy license.
As much as I think it would be infinitely cooler if Hasbro tried to capture my limited D&D dollars by making an awesome theme park happen (through licensing), than by trying to fleece me with some online services I don't want or need, they seem pretty hellbent on the latter option.