There are many Western themed movies both live action and animated. PATF is not even close to Western themed. A huge collaboration of movies such as Lone Ranger, Zorro, The Apple Dumpling Gang, Home on the Range, and many more could be organized together like great movie ride as a tribute to that genre in Disney films.
There are a lot of angles you can go at criticizing this move. But concern for theming is SO WEAK. And frankly holds little water in my opinion.
Exploration of the Frontier started with the Louisiana Purchase.
Tom Sawyer Island and the Riverboat is also mostly based on Mississippi and Missouri. As someone else pointed out, St. Louis to New Orleans was one of the biggest routes of steamboats.
Im not sure how a swampy bayou Louisiana theme is so much of a stretch to fit in there. As long as they stick to the Swamp/Bayou theming only and leave out New Orleans city itself, it will fit seamlessly.
Adventureland includes Jungle, Middle Eastern Bazar, and then Caribbean island theming right on top of each other. They all blend seamlessly. And it wasn't always themed that way originally, but they made the added themes blend.
Now, if you never realized that they stacked the Middle East on top of the Caribbean and instead you just thought of it all as Adventureland, then maybe calm down about this much less egregious theming clash.
I love Splash Mountain, but ppl seem to be saying that the new theme is a WILDLY different aesthetic than what is there now. Which just isnt the case. Bayou/Lousiana swamp fits right in with the Riverboat and Tom Sawyer Island far more than Big Thunder Mountain southwest desert theme does honestly.
Like, cheaply re-theme Pecos Bill into cajun food(Call it Mama Odie's or something) and you have a perfect little sub section as a buffer between the Caribbean theming and the Desert. A sub section that fits with the Riverboat and the Island across the river pretty well.
Adjust traffic flow a tiny bit and it easily flows together.