Maybe the difference is if it's original works vs a painting of a real landscape. If its all an artwork with no real locations in it, you can copyright the whole artwork, designs, colours, etc. Otherwise, you can still trademark the artwork itself to protect against reproduction, but you can't trademark the real area like buildings, etc. So, if you took the same artwork of the original emerald city and used it as the front for the ride, it's not a real place, so the artwork and design is probably copyrighted and can't just be reproduced. I think this was the issue with the movie disney made? They had to tread a real fine line between anything that looked like the 1939 movie.
You're still floating for the most part, just you might feel the bottom sometimes. You know what really removes the immersion? The ride being closed for good because there are safety concerns. Which do you want? live with the changes or have no ride at all?
The answer is yes. Have you seen it/ridden it? Its not really themed as well as west and overall it is a smaller ride, but the same thing seems to have happened.
I know their boats aren't as big so it might not work, but one thing that would have been amazing is to swap the chain drive of west for lift conveyors used in rio bravo.