Dev blog over here
The taxidermist has very little to offer to the game right now. Because trophy prices don't fluctuate so wildly anymore the information he provides is just a completion list, and is completely meaningless after you've defeated Horatio. His only purpose is figuring out which trophies you need to access Horatio, which is pretty narrow and something you may only need to check on three or four times ever.
I'd think you will need to add some new feature to his building to get people to use it with any degree of frequency, or else change the way trophies work (again...)