And? It's a tiny house. Lupin wasn't using it as a safehouse during his time at Hogwarts. There's no attraction to be made from it. I'm all for a small façade ala the Psycho house back in the day, but it's not attraction material.
I never said E-ticket attraction or ride in general. Just an attraction in and of its own. Go in there, see Lupin's son who teaches you a bit on the other things in the wizard world such as werewolves and all of a sudden transformation.
The only thing was the betrayal. The transformation happened outside closer to the castle and Voldemort's "command center" was the Riddle family home.
No, Lupin used to transform in the Shrieking Shack back in the day which is why people thought it was haunted. Its literally quoted in the book and way all his friends transformed into animals.