I don't think it's cancelled at this time, but the art (all of it, I believe) was for Disneyland's attraction.
If you look at the logs in the recent art work, they were single file, which matches California's version of the ride. I haven't seen any Florida-specific art to date, which given it's a different ride, it would need its own design. That's not to say they haven't done work on Florida's project, but they haven't shown much proof of it.
They also had some vague art work, multiple videos, and a D23 announcement for the Mary Poppins attraction in Epcot, which was specific to Florida. They also released art work for the Main Street Theater along with a D23 announcement. So, that doesn't really mean all that much long term if the person pushing this project won't be around to see it through and it's looking like Iger might actually be leaving this time.
It could simply, instead of getting cancelled, get pushed back for a long while in favor of other things that will do more to drive attendance and sell merchandise. Not saying that Tiana wouldn't sell merchandise, she absolutely would in the US... she already does without an attraction.
Really, if they wanted to capitalize on Tiana, from a business perspective, they need to build Tiana's Place. It doesn't have to be lumped in with the Splash Mountain project either, they could do it as its own project and give it a quicker timeline. If there's a Tiana project that I think all guests want, it's definitely that and it'll make some extra money, which I'm sure Chapek would love.