I think it´s not possible to predict what Jungels, Dombrowski and others will do, th start from zero by entering the pro peloton.
Looking at the guys who´ve already ridden one or two pro seasons, I don´t really see anyone who´ll dominate everything, but that doesn´t mean anything.
Ullrich was second in his first ever Tour in 1996, aged 22, whereas Contador and Rasmussen needed some time to become dominators.
Andy Schleck was maybe similar to Ullrich, being top nearly already from the beginning.
The problem with predictions is that GT top riders peak from 27/28 to 32, so we won´t really know before.
In the next years, it will remain between Contador, A.Schleck, Froome, Wiggins, VDB, Van Garderen, Kreuziger, maybe Fuglsang, and few others.