I think it's much more important to learn to draw and paint with physical materials before you jump to digital work.
I disagree with this. I don't see a "jump" between digital and physical work. To me they're just two different types of medium. Would you say it's important to learn to use pencils before you can use pens, or to draw before you can sculpt or do collage? An understanding of a wide range of media is important, and you'll grow better as an artist with a more diverse eye.
There's no hierarchy of materials, or a difficulty list from easy to hard. There's just different kinds of materials with different properties which can help you learn different lessons as an artist. Digital drawing is a fun medium which offers up some really sweet opportunities for experimentation