One of my other favorite point and click adventure games also suffered from this transition to 3D: King's Quest. King's Quest 7 was a beautifully hand-drawn animated storybook that looked like an old school Disney feature film. King's Quest 8 was hideous 3D garbage that looked bland and worse, they changed the whole premise of the series to focus more on combat than puzzles and storyline.

That being said, I think modern 3D games look fantastic when done correctly. It's just not the best format for some genres.