I have no issue with space, resources, or effort being deployed for a walk through attraction. Disneyland Paris has many, and they are wonderful.
There's a lot of difference between Journey of Water and the DLP walkthroughs.
The DLP Walkthroughs are all sumptuous, high-quality, inexpensive . . . they contribute directly to the theme of their land, fulfill an aspirational moment relative to their theme, and only one of them opened as a standalone offering - Les Mysteres du Nautilus, which opened during the construction of their Space Mountain in anticipation of needing to be able to handle more crowds in that corner of the park in 11 months when Space would be complete. They're each tucked in corners that are not really large enough for alternate use, and sometimes hidden in plain sight offering an opportunity to explore spaces that the Stateside parks would mostly leave empty. None of these attractions were marketed heavily (though of course the landscape was different then without Social Media), and all of them were meant to address the pressing capacity concerns of the park. The financial failure of EuroDisneyland is usually painted with a brush that glosses over the details - they built far too much hotel space given most guests were either local or chose to stay offsite in the City, which put the overall resort in the red, but the Park itself did gangbusters from day one. They needed more places for guests to be, and fast, hence the greenlighting of additional walkthroughs that could open in the first 2 years of the park. The ones that opened with the park - the Castle Walkthrough, the Dragon's Lair, and Alice's Curious Labyrinth, the Swiss Family Robinson Treehouse, and (arguably) Adventure Isle - were all solid if minor offerings that were complemented by a healthy menu of attractions throughout DLP. In the early days The Dragon's Lair in particular was cited as the #3 attraction in the whole park in terms of guest satisfaction, so it far outperformed expectations.
Meanwhile EPCOT's new walkthrough appears to be far too little too late on nearly every front, excepting expense and footprint -
EPCOT has been faltering thematically for years, with neither guests nor management seeming to know what the park should actually be, and Moana only contributes to that confusion. The park is short on meaningful attractions that draw guests in, and not making full use of the capacity it already offers, so adding "just anything" is not what's needed. While the rockwork and foliage appear nice on their own, they're stuck in a spot that offer few clues as to why they're there. They've added one of their most popular properties to the marquee despite the attraction making no real attempt to deliver a genuinely satisfying "Moana" experience. Despite this, the attraction has managed to cost many millions of dollars - far more than any of the DLP walkthroughs. Construction has taken many years on what amounts to an outdoor queue for a larger attraction that doesn't actually exist, and that process has been charted by Disney and fans alike, creating an outsized impression of the attraction's significance. The attraction seems to be pulling from a bag of tricks that its neighbor has already been offering for 40 years. Due to its placement, it physically is the literal centerpiece attraction of what was meant to be the parks revitalization plan, hardly any of which came to pass. That real estate could and should have been used on an attraction that helps state clearly what the new direction of the park is. Instead JoW merely suggests that EPCOT is a place you can find characters, but the logic of who and why remains pretty mysterious. On top of that, the people who are most likely to see through those mistakes and hiccups to evaluate the attraction on the level it was meant to be appraised (The Cast and their guests) are saying it
still manages to underwhelm. The uninitiated guest that thinks this is a new "Moana Ride" is not going to be so kind.
I'm sure I'll be able to enjoy Journey of Water for what it is, but the DLP Walkthroughs are like the sprinkles on an already fabulous cake. Journey of Water . . . has not been set up to be that.