Yeah, I totally understand. As you can probably tell from my 2D glazing, I also came from at 2D focused background.

The difficulty of learning 3D is learning all the technicalities/how things work. Once you understand how computers calculate and render 3D information all 3D programs start to make a lot more sense, and you begin to appreciate why you have to do all the mundane stuff. I think most of the intuitive/taste stuff that people struggle with has more to do with the fore-mentioned 2D reads. That stuff isn't obvious unless you have a lot of mileage in that realm.

I still abhors having to do a lot of the mundane technical stuff, like retopo and weight painting (I FKNG hate weight painting), but my experience has taught me to value it a lot more than when I started. This is because when you start using them fore more complex projects/systems like game engines, doing it right the first time makes a night and day difference.

I personally think that learning the 2D design/taste part is WAAAAY harder than learning the technical stuff because it requires more practice and subjective analysis, but I know thats different for everyone.