Everybody always adds this little thing. Who gives AF about what Rowling wants or likes. It's not up to her. I'm sure when Disney has construction going on, Walt wouldn't like a large crane shooting out of the background of the castle, but it has to happen. Progress needs to go on because you can't just make a crane invisible. It's up to universal to make it a seamless as possible, but they can't just magically make a ride appear without having construction done.
I think the post you're addressing incorrectly addresses Rowling's pickiness. Though Universal definitely cares about her view (because she does have a fair amount of weight on the authenticity aspect), she's not as unrealistic about things as some people like to make her out. There have been multiple construction walls before for Potter and I honestly believe she is fine with that.
Now whatever replaces Dragon Challenge will have to fit authentically in the space. That really means the Forest in the end. Maybe a few new Hogsmeade locations but mostly the forest and potentially an expansion of Hogwarts but I doubt that...