What Are European Advanced and Expert Pistes Like?

In the Western US advanced terrain is nearly all moguls, glades, or other ungroomed or minimally groomed runs. Expert terrain is usually usually wild stuff, steep trees, cliffs, chutes, etc. Groomed advanced pistes are rare and in many resorts cannot be found. I've never seen a groomed expert run.

What makes European expert and advanced terrain...well... expert snd advanced? It seems like almost all runs are groomed pistes. Is it mostly steepness?