I created a new MVC site on 12.0.31 and experienced the same problem. Just tried upgrading to 12.0.38 ... still no dice.
Turns out I did a dumb thing which took me far longer than it should have for me to realize. Because this was my first time getting a page on my new MVC site to load, I didn't actually know if everything was setup correctly. Turns out it wasn't, no shocker there. Long story short, make sure your IIS site is looking not at the solution folder, but the mvc project folder. This folder didn't exist when I created the IIS site bc I set that up before creating the project in Visual Studio.